Stepwise assembly of a semiconducting coordination polymer [Cd8S(SPh)14(DMF)(bpy)]n and its photodegradation of organic dyes.

PubMed

Xu, Chao; Hedin, Niklas; Shi, Hua-Tian; Xin, ZhiFeng; Zhang, Qian-Feng

2015-04-14

Chalcogenolate clusters can be interlinked with organic linkers into semiconducting coordination polymers with photocatalytic properties. Here, discrete clusters of Cd8S(SPh)14(DMF)3 were interlinked with 4,4'-bipyridine into a one dimensional coordination polymer of [Cd8S(SPh)14(DMF)(bpy)]n with helical chains. A stepwise mechanism for the assembly of the coordination polymer in DMF was revealed by an ex situ dynamic light scattering study. The cluster was electrostatically neutral and showed a penta-supertetrahedral structure. During the assembly each cluster was interlinked with two 4,4'-bipyridine molecules, which replaced the two terminal DMF molecules of the clusters. In their solid-state forms, the cluster and the coordination polymer were semiconductors with wide band gaps of 3.08 and 2.80 ev. They photocatalytically degraded rhodamine B and methylene blue in aqueous solutions. The moderate conditions used for the synthesis could allow for further in situ studies of the reaction-assembly of related clusters and coordination polymers.

Double layer zinc-UDP coordination polymers: structure and properties.

PubMed

Qiu, Qi-Ming; Gu, Leilei; Ma, Hongwei; Yan, Li; Liu, Minghua; Li, Hui

2018-05-17

A homochiral Zn-UDP coordination polymer with an alternating parallel ABAB sequence was constructed and studied by X-ray single crystal diffraction analysis. Its crystal structure shows that there are potentially open sites in the 2D layers. The activation of the sites makes the coordination polymer a fluorescent sensor for novel heterogeneous detection of amino acids.

Coordinative nanoporous polymers synthesized with hydrogen-bonded columnar liquid crystals.

PubMed

Ishihara, Shinsuke; Furuki, Yusuke; Hill, Jonathan P; Ariga, Katsuhiko; Takeoka, Shinji

2012-10-01

In this paper, we report the development of nanoporous polymer which demonstrates the coordination property toward zinc porphyrin. A hydrogen-bonded columnar liquid crystalline precursor composed of a triphenylene template and three equivalent of the surrounding dendric amphiphile bearing a pyridyl head group and a polymerizable aliphatic chain, was covalently fixed by photopolymerization, and then the subsequent selective removal of the template successively resulted in a nanoporous polymer in which the pore wall is modified with pyridyl groups. The nanoporous polymer reflected the conformation of template, and displayed considerable coordination ability of the pyridyl groups towards zinc porphyrin. The coordinative nanoporous polymer is promising as a nano-scaled scaffold for the organization of dyes into functional supramolecular architectures.

Polymer complexes.. XXXX. Supramolecular assembly on coordination models of mixed-valence-ligand poly[1-acrylamido-2-(2-pyridyl)ethane] complexes

NASA Astrophysics Data System (ADS)

El-Sonbati, A. Z.; El-Bindary, A. A.; Diab, M. A.

2003-02-01

The build-up of polymer metallic supramolecules based on homopolymer (1-acrylamido-2-(2-pyridyl)ethane (AEPH)) and ruthenium, rhodium, palladium as well as platinum complexes has been pursued with great interest. The homopolymer shows three types of coordination behaviour. In the mixed valence paramagnetic trinuclear polymer complexes [( 11)+( 12)] in the paper and in mononuclear polymer complexes ( 1)-( 5) it acts as a neutral bidentate ligand coordinating through the N-pyridine and NH-imino atoms, while in the mixed ligand diamagnetic poly-chelates, which are obtained from the reaction of AEPH with PdX 2 and KPtCl 4 in the presence of N-heterocyclic base consisting of polymer complexes ( 9)+( 10), and in monouclear compounds ( 6)-( 8), it behaves as a monobasic bidentate ligand coordinating through the same donor atoms. In mononuclear compounds ( 13)+( 14) it acts as a monobasic and neutral bidentate ligand coordinating only through the same donor atoms. Monomeric distorted octahedral or trimeric chlorine-bridged, approximately octahedral structures are proposed for these polymer complexes. The poly-chelates are of 1:1, 1:2 and 3:2 (metal-homopolymer) stoichiometry and exhibit six coordination. The values of ligand field parameters were calculated. The homopolymer and their polymer complexes have been characterized physicochemically.

Polymer complexes. XXXX. Supramolecular assembly on coordination models of mixed-valence-ligand poly[1-acrylamido-2-(2-pyridyl)ethane] complexes.

PubMed

El-Sonbati, A Z; El-Bindary, A A; Diab, M A

2003-02-01

The build-up of polymer metallic supramolecules based on homopolymer (1-acrylamido-2-(2-pyridyl)ethane (AEPH)) and ruthenium, rhodium, palladium as well as platinum complexes has been pursued with great interest. The homopolymer shows three types of coordination behaviour. In the mixed valence paramagnetic trinuclear polymer complexes [(11)+(12)] in the paper and in mononuclear polymer complexes (1)-(5) it acts as a neutral bidentate ligand coordinating through the N-pyridine and NH-imino atoms, while in the mixed ligand diamagnetic poly-chelates, which are obtained from the reaction of AEPH with PdX2 and KPtCl4 in the presence of N-heterocyclic base consisting of polymer complexes (9)+(10), and in monouclear compounds (6)-(8), it behaves as a monobasic bidentate ligand coordinating through the same donor atoms. In mononuclear compounds (13)+(14) it acts as a monobasic and neutral bidentate ligand coordinating only through the same donor atoms. Monomeric distorted octahedral or trimeric chlorine-bridged, approximately octahedral structures are proposed for these polymer complexes. The poly-chelates are of 1:1, 1:2 and 3:2 (metal-homopolymer) stoichiometry and exhibit six coordination. The values of ligand field parameters were calculated. The homopolymer and their polymer complexes have been characterized physicochemically.

Solvent induced synthesis, structure and properties of coordination polymers based on 5-hydroxyisophthalic acid as linker and 1,10-phenanthroline as auxiliary ligand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kariem, Mukaddus; Yawer, Mohd; Sheikh, Haq Nawaz, E-mail: hnsheikh@rediffmail.com

2015-11-15

Three new coordination polymers [Mn(hip)(phen) (H{sub 2}O)]{sub n} (1), [Co(hip)(phen) (H{sub 2}O)]{sub n} (2), and [Cd(hip) (phen) (H{sub 2}O)]{sub n} (3) (H{sub 2}hip=5-hydroxyisophthalic acid; phen=1,10-phenanthroline) have been synthesized by solvo-hydrothermal method using diethyl formamide-water (DEF-H{sub 2}O) as solvent system. Single-crystal X-ray diffraction analysis reveals that all three coordination polymers 1, 2 and 3 crystallize in monoclinic space group P2/n. Metal ions are inter-connected by hydroxyisophthalate anions forming zig-zag 1D chain. 1D chains are further inter-connected by hydrogen bonding and π–π stacking interactions leading to 3D supramolecular architecture. Hydrogen-bonding and π–π stacking provide thermal stability to polymers. Compounds 1 and 2more » are paramagnetic at room temperature and variable temperature magnetic moment measurements revealed weak ferromagnetic interactions between metal ions at low temperature. Compound 3 exhibits excellent photoluminescence with large Stokes shift. - Graphical abstract: 1D helical chains of coordination polymers were synthesized by solvo-hydrothermal reaction of 5-hydroxyisopthalic acid and 1,10-phenanthroline with MnCl{sub 2}·4H{sub 2}O / CoCl{sub 2}·6H{sub 2}O / Cd(NO{sub 3}){sub 2}·6H{sub 2}O. - Highlights: • Solvent induced synthesis of three coordination polymers with 1D zig-zag structure. • Crystal structures of coordination polymers are reported and discussed. • 1,10-Phenanthroline influences magnetic and luminescent properties of polymers. • Coordination polymer of Cd is luminescent exhibiting large Stokes shift.« less

Tellurium-containing polymer micelles: competitive-ligand-regulated coordination responsive systems.

PubMed

Cao, Wei; Gu, Yuwei; Meineck, Myriam; Li, Tianyu; Xu, Huaping

2014-04-02

Nanomaterials capable of achieving tunable cargo release kinetics are of significance in a fundamental sense and various biological or medical applications. We report a competitive coordination system based on a novel tellurium-containing polymer and its ligand-regulated release manners. Tellurium was introduced to water-soluble polymers for the first time as drug delivery vehicles. The coordination chemistry between platinum and tellurium was designed to enable the load of platinum-based drugs. Through the competitive coordination of biomolecules, the drugs could be released in a controlled manner. Furthermore, the release kinetics could be modulated by the competitive ligands involved due to their different coordination ability. This tellurium-containing polymer may enrich the family of delivery systems and provide a new platform for future biomedical nanotechnologies.

Synthesis, structure, and luminescence property of a series of Ag–Ln coordination polymers with the N-heterocyclic carboxylato ligand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin, Jing, E-mail: jinjing_crystal@126.com; Chen, Chong; Gao, Yan

Six Ln–Ag coordination polymers {[LnAg_2(IN)_4(H_2O)_5]·NO_3·2H_2O}{sub n} (Ln=Ho (1) and Tb (2), HIN=isonicotinic acid), {[PrAg_2(IN)_4(H_2O)_2]·NO_3·H_2O}{sub n} (3), [LnAg(pdc){sub 2}]{sub n} (Ln=Eu(4) and Pr (5), H{sub 2}pdc=3,4-pyridine-dicarboxylic acid) and [NdAg(bidc){sub 2}(H{sub 2}O){sub 4}]{sub n} (6) (H{sub 2}bidc=benzimidazole-5,6-dicarboxylic acid) have been hydrothermally synthesized and characterized by single crystal X-ray diffraction, elemental analysis, IR, UV–vis-NIR absorption spectra, fluorescence spectra and thermogravimetric analysis. Structural analyses reveal that the six polymers exhibit 0D (polymer (1)), 1D (polymer (2)), 2D (polymers (3) and (5)) and 3D (polymers (4) and (6)) infinite structures, respectively. Polymers (1)–(6) exhibit the Ln(III) characteristic emission in the near-infrared (NIR) region or inmore » the visible region. Especially, the NIR emission bands of polymers 1, 5 and 6 evidently present shift or splitting due to formation of the Ln–Ag coordination polymers. This can be attributed to the tune of inner levels in Ln–Ag system caused by the interact and influence between the 4d orbital of the Ag(I) ion and the 4f orbital of the Ln(III) ion, which can be confirmed by the UV–vis-NIR absorption spectra of the polymers. In addition, the distortion of coordination geometry as well as difference of the coordination number around the Ag(I) ion affect the structure framework. - Graphical abstract: Six Ag–Ln coordination polymers have been hydrothermally synthesized and characterized. The photoluminescence properties were studied. The distortion of coordination geometry of Ag(I) ion affect structure framework. Introduction of Ag(I) cause wonderful changes to the NIR emission of Ln(III) ions. - Highlights: • Six Ln–Ag polymers have been synthesized and characterized. • The distortion of coordination geometry of Ag(I) ion affect structure framework. • Introduction of Ag(I) cause wonderful changes to the NIR emission of Ln(III) ions.« less

Chemical anchoring of organic conducting polymers to semiconducting surfaces

DOEpatents

Frank, A.J.; Honda, K.

1984-01-01

According to the present invention, an improved method of coating electrodes with conductive polymer films and/or preselected catalysts is provided. The charge conductive polymer is covalently or coordinatively attached to the electrode surface to strengthen the adhesion characteristics of the polymer to the electrode surface or to improve charge conductive properties between the conductive polymer and the electrode surface. Covalent or coordinative attachment is achieved by a number of alternative methods including covalently or coordinatively attaching the desired monomer to the electrode by means of a suitable coupling reagent and, thereafter, electrochemically polymerizing the monomer in situ.

Chemical anchoring of organic conducting polymers to semiconducting surfaces

DOEpatents

Frank, Arthur J.; Honda, Kenji

1984-01-01

According to the present invention, an improved method of coating electrodes with conductive polymer films and/or preselected catalysts is provided. The charge-conductive polymer is covalently or coordinatively attached to the electrode surface to strengthen the adhesion characteristics of the polymer to the electrode surface or to improve charge-conductive properties between the conductive polymer and the electrode surface. Covalent or coordinative attachment is achieved by a number of alternative methods including covalently or coordinatively attaching the desired monomer to the electrode by means of a suitable coupling reagent and, thereafter, electrochemically polymerizing the monomer in situ.

Highly luminescent and triboluminescent coordination polymers assembled from lanthanide β-diketonates and aromatic bidentate O-donor ligands.

PubMed

Eliseeva, Svetlana V; Pleshkov, Dmitry N; Lyssenko, Konstantin A; Lepnev, Leonid S; Bünzli, Jean-Claude G; Kuzmina, Natalia P

2010-10-18

The reaction of hydrated lanthanide hexafluoroacetylacetonates, [Ln(hfa)(3)(H(2)O)(2)], with 1,4-disubstituted benzenes afforded a new series of one-dimensional coordination polymers [Ln(hfa)(3)(Q)](∞), where Ln = Eu, Gd, Tb, and Lu and Q = 1,4-diacetylbenzene (acbz), 1,4-diacetoxybenzene (acetbz), or 1,4-dimethyltherephtalate (dmtph). X-ray single crystal analyses reveal [Ln(hfa)(3)(acbz)](∞) (Ln = Eu, Gd, Tb) consisting of zigzag polymeric chains with Ln-Ln-Ln angles equal to 128°, while the arrays are more linear in [Eu(hfa)(3)(acetbz)](∞) and [Eu(hfa)(3)(dmtph)](∞), with Ln-Ln-Ln angles of 165° and 180°, respectively. In all structures, Ln(III) ions are 8-coordinate and lie in distorted square-antiprismatic environments. The coordination polymers are thermally stable up to 180-210 °C under a nitrogen atmosphere. Their volatility has been tested in vacuum sublimation experiments at 200-250 °C and 10(-2) Torr: the metal-organic frameworks with acetbz and dmtph can be quantitatively sublimed, while [Ln(hfa)(3)(acbz)](∞) undergoes thermal decomposition. The triplet state energies of the ancillary ligands, 21,600 (acetbz), 22,840 (acbz), and 24,500 (dmtph) cm(-1), lie in an ideal range for sensitizing the luminescence of Eu(III) and/or Tb(III). As a result, all of the [Ln(hfa)(3)(Q)](∞) polymers display bright red or green luminescence due to the characteristic (5)D(0) → (7)F(J) (J = 0-4) or (5)D(4) → (7)F(J) (J = 6-0) transitions, respectively. Absolute quantum yields reach 51(Eu) and 56(Tb) % for the frameworks built from dmtph. Thin films of [Eu(hfa)(3)(Q)](∞) with 100-170 nm thickness can be obtained by thermal evaporation (P < 3 × 10(-5) Torr, 200-250 °C). They are stable over a long period of time, and their photophysical parameters are similar to those of the bulk samples so that their use as active materials in luminescent devices can be envisaged. Mixtures of [Ln(hfa)(3)(dmpth)](∞) with Ln = Eu and Tb yield color-tunable microcrystalline materials from red to green. Finally, the crystalline samples exhibit strong triboluminescence, which could be useful in the design of pressure and/or damage detection probes.

Metal-coordination: Using one of nature’s tricks to control soft material mechanics

PubMed Central

Holten-Andersen, Niels; Jaishankar, Aditya; Harrington, Matthew; Fullenkamp, Dominic E.; DiMarco, Genevieve; He, Lihong; McKinley, Gareth H.; Messersmith, Phillip B.; Lee, Ka Yee C.

2015-01-01

Growing evidence supports a critical role of dynamic metal-coordination crosslinking in soft biological material properties such as self-healing and underwater adhesion1. Using bio-inspired metal-coordinating polymers, initial efforts to mimic these properties have shown promise2. Here we demonstrate how bio-inspired aqueous polymer network mechanics can be easily controlled via metal-coordination crosslink dynamics; metal ion-based crosslink stability control allows aqueous polymer network relaxation times to be finely tuned over several orders of magnitude. In addition to further biological material insights, our demonstration of this compositional scaling mechanism should provide inspiration for new polymer material property-control designs. PMID:26413297

Room temperature synthesis of a Zn(II) metal-organic coordination polymer for dye removal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abbasi, Alireza, E-mail: aabbasi@khayam.ut.ac.ir; Gharib, Maniya; Najafi, Mahnaz

2016-03-15

A new one-dimensional (1D) coordination polymer, [Zn(4,4′-bpy)(H{sub 2}O){sub 4}](ADC)·4H{sub 2}O (1) (4,4′-bpy=4,4′-bipyridine and H{sub 2}ADC=acetylenedicarboxylic acid), was synthesized at room temperature. The crystal structure of the coordination polymer was determined by single-crystal X-ray diffraction analysis. Compound 1 was also characterized by FT-IR, powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA). The catalytic activity of 1 was evaluated in the color removal of Bismarck brown as a representative of dye pollutant in water under mild conditions. Coordination polymer 1 exhibited good catalytic activity and stability in the decolorization of Bismarck brown and could be easily recovered and reused for at leastmore » three cycles. - Graphical abstract: A new 1D coordination polymer as catalyst for the degradation of Bismarck brown aqueous solution. - Highlights: • A 1D coordination polymer has been synthesized at room temperature. • The prepared compound was utilized for color removal of Bismarck brown dye. • Good catalytic activity and stability in the dye decolorization has been found.« less

Coordination-supported organic polymers: mesoporous inorganic–organic materials with preferred stability

DOE PAGES

Chen, Dong; Zhang, Pengfei; Fang, Qianrong; ...

2018-01-01

A simple and versatile strategy is developed for the synthesis of coordination-supported organic polymers(COPs) via coordination between Al 3+ and 5-amino-8-hydroxyquinoline together with organic imine- or imide-based polycondensation.

Coordination-supported organic polymers: mesoporous inorganic–organic materials with preferred stability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Dong; Zhang, Pengfei; Fang, Qianrong

A simple and versatile strategy is developed for the synthesis of coordination-supported organic polymers(COPs) via coordination between Al 3+ and 5-amino-8-hydroxyquinoline together with organic imine- or imide-based polycondensation.

Cobalt-cadmium bimetallic porphyrin coordination polymers for electrochemistry application

NASA Astrophysics Data System (ADS)

Wang, C. Y.; Cui, G. Y.; Ding, D.; Zhou, B.

2018-01-01

In this paper, we used tetra (4-carboxyphenyl) porphyrin (H2TCPP) and metal cadmium, cobalt as reactants to synthesize metal porphyrin coordination polymers that they had different metal ratio. They were expressed as Co1Cd3TCPP, Co1Cd1TCPP, Co3Cd1TCPP, respectively. The results were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and inductively coupled plasma atomic emission spectrometer (ICP). Herein, a series of metal porphyrin coordination polymers has multiple metal active centers and constructs electrochemistry sensors. In order to increase the conductivity, multi-walled carbon nanotubes (MWCNTs) can be used to modify the electrodes. The polymer/MWCNTs/GCE electrode was studied by cyclic voltammetry and chronoamperometry as sensor for sodium nitrite. The performance of Co1Cd1TCPP/MWCNTs/GCE electrode is best, the sensitivity for sodium nitrite is 350.95 mA M-1 cm-2 and the. The results indicate that metal porphyrin coordination polymers have excellent performance. It also enriches the application of metal porphyrin coordination polymer in electrochemistry sensor.

Design and its limitations in the construction of bi- and poly-nuclear coordination complexes and coordination polymers (aka MOFs): a personal view.

PubMed

Robson, R

2008-10-14

This article, presented from a personal point of view, is concerned with the design of ligands intended to give specifically either binuclear or tetranuclear metal complexes or coordination polymers. No attempt is made to provide a comprehensive coverage of these topics, the focus being mainly upon results from our laboratory. Some emphasis is placed upon aspects of the historical development of the deliberate construction of coordination polymers (aka MOFs)--materials promising useful applications, the study of which continues to expand exponentially. Some of our recent research is described in which the carbonate ion and the tetracyanoquinodimethane dianion are used as bridging ligands to generate targeted coordination polymers. It is intended that Dalton Perspectives be easily comprehensible to non-specialists in the field; an average second year university chemistry student should be easily able to understand the present contribution.

Bio-inspired Self-healing Composite Hydrogel with Iron Oxide Nanoparticle as Coordination Crosslinker

NASA Astrophysics Data System (ADS)

Li, Qiaochu; Barret, Devin G.; Messersmith, Phillip B.; Holten-Andersen, Niels

2014-03-01

Polymer-nanoparticle (NP) composites have attracted renewed attention due to enhanced mechanical strength combined with various functionalities, but controlling the interfacial chemistry between NPs and polymer matrix, which is crucial for the composite's mechanical behavior, remains a major challenge. Inspired by the adhesion chemistry of mussel fibers, we investigated a novel approach to incorporate Fe3O4 NPs into hydrogel matrix. A polyethylene glycol polymer is designed with both ends conjugated by catechol groups, which have strong coordination affinity to Fe. The polymer network is crosslinked via coordination bonding at the surface of Fe3O4 NPs, yielding a stiff nanocomposite hydrogel. Due to the reversible nature of coordination bonding, the hydrogel presents self-healing behavior. Oscillatory rheology allows comparative kinetic studies of self-healing driven by catechol bonding at Fe3O4 NP interfaces and by catechol-Fe3+ coordination complexes. Furthermore, the superparamagnetic property of Fe3O4 NP is preserved after gelation, allowing for response to external stimuli. This gelation motif can serve as a versatile platform for tuning functional and mechanical properties for future polymer nanocomposite materials.

Linking 1D Transition-Metal Coordination Polymers and Different Inorganic Boron Oxides To Construct a Series of 3D Inorganic-Organic Hybrid Borates.

PubMed

Zhi, Shao-Chen; Wang, Yue-Lin; Sun, Li; Cheng, Jian-Wen; Yang, Guo-Yu

2018-02-05

Three inorganic-organic hybrid borates, M(1,4-dab)[B 5 O 7 (OH) 3 ] [M = Zn (1), Cd (2), 1,4-dab = 1,4-diaminobutane)] and Co(1,3-dap)[B 4 O 7 ] (3, 1,3-dap = 1,3-diaminopropane), which integrated characteristics of 1D coordination polymers and 1D/3D inorganic boron oxides have been obtained under solvothermal conditions. Compounds 1 and 2 are isostructural and crystallize in a centrosymmetric space group P2 1 /c; the 3D achiral structures of 1 and 2 consist of the nonhelical Zn/Cd-1,4-dap coordination polymers and 1D B-O chains. Compound 3 crystallizes in a chiral space group P4 3 2 1 2; the helical Co-1,3-dap coordination polymer chains are entrained within a 3D B-O network and finally form the chiral framework. Compounds 1-3 represent good examples of using coordination polymers to construct mixed-motif inorganic-organic hybrid borates. Compounds 1 and 2 display blue luminescence when excited with UV light.

Aromatic carboxylate effect on dimensionality of three bis(benzimidazole)-based cobalt(II) coordination polymers: Syntheses, structures and properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Ju-Wen; Gong, Chun-Hua; Hou, Li-Li

2013-09-15

Three new metal-organic coordination polymers [Co(4-bbc){sub 2}(bbbm)] (1), [Co(3,5-pdc)(bbbm)]·2H{sub 2}O (2) and [Co(1,4-ndc)(bbbm)] (3) (4-Hbbc=4-bromobenzoic acid, 3,5-H{sub 2}pdc=3,5-pyridinedicarboxylic acid, 1,4-H{sub 2}ndc=1,4-naphthalenedicarboxylic acid and bbbm=1,1-(1,4-butanediyl)bis-1H-benzimidazole) were hydrothermally synthesized and structurally characterized. Polymer 1 is a 1D chain formed by the bbbm ligands and Co{sup II} ions. Polymer 2 exhibits a 2D network with a (3·4·5)(3{sup 2}·4·5·6{sup 2}·7{sup 4}) topology. Polymer 3 possesses a 3D three-fold interpenetrating framework. The versatile structures of title polymers indicate that the aromatic carboxylates have an important influence on the dimensionality of 1–3. Moreover, the thermal stability, electrochemical and luminescent properties of 1–3 were investigated. - graphicalmore » abstract: Three bis(benzimidazole)-based cobalt(II) coordination polymers tuned by aromatic carboxylates were hydrothermally synthesized and structurally characterized. The aromatic carboxylates play a key role in the dimensionality of three polymers. The electrochemical and luminescent properties of three polymers were investigated. Display Omitted - Highlights: • Three bis(benzimidazole)-based cobalt(II) coordination polymers tuned by aromatic carboxylates were obtained. • The aromatic carboxylates have an important influence on the dimensionality of three polymers. • The electrochemical and luminescent properties of three polymers were investigated.« less

Three-dimensional iron(ii) porous coordination polymer exhibiting carbon dioxide-dependent spin crossover.

PubMed

Shin, Jong Won; Jeong, Ah Rim; Jeoung, Sungeun; Moon, Hoi Ri; Komatsumaru, Yuki; Hayami, Shinya; Moon, Dohyun; Min, Kil Sik

2018-04-24

We report a three-dimensional Fe(ii) porous coordination polymer that exhibits a spin crossover temperature change following CO2 sorption (though not N2 sorption). Furthermore, single crystals of the desolvated polymer with CO2 molecules at three different temperatures were characterised by X-ray crystallography.

Redox-active porous coordination polymer based on trinuclear pivalate: Temperature-dependent crystal rearrangement and redox-behavior

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lytvynenko, Anton S.; Kiskin, Mikhail A., E-mail: mkiskin@igic.ras.ru; Dorofeeva, Victoria N.

2015-03-15

Linking of trinuclear pivalate Fe{sub 2}NiO(Piv){sub 6} (Piv=O{sub 2}CC(CH{sub 3}){sub 3}) by 2,6-bis(4-pyridyl)-4-(1-naphthyl)pyridine (L) resulted in formation of 1D-porous coordination polymer Fe{sub 2}NiO(Piv){sub 6}(L)·Solv, which was characterized in two forms: DMSO solvate Fe{sub 2}NiO(Piv){sub 6}(L)(DMSO)·2.5DMSO (1) or water solvate Fe{sub 2}NiO(Piv){sub 6}(L)(H{sub 2}O) (2). X-ray structure of 1 was determined. Crystal lattice of 1 at 160 K contained open channels, filled by captured solvent, while temperature growth to 296 K led to the crystal lattice rearrangement and formation of closed voids. Redox-behavior of 2 was studied by cyclic voltammetry for a solid compound, deposited on glassy-carbon electrode. Redox-activity of Lmore » preserved upon incorporation in the coordination polymer. The presence of pores in desolvated sample Fe{sub 2}NiO(Piv){sub 6}(L) was confirmed by the measurements of N{sub 2} and H{sub 2} adsorption at 77 K. Potential barriers of the different molecules diffusion through pores were estimated by the means of molecular mechanics. - Graphical abstract: Redox-behavior of 1D-porous coordination polymer Fe{sub 2}NiO(Piv){sub 6}(L)(H{sub 2}O) was studied by cyclic voltammetry in thin film, deposited on glassy-carbon electrode. Redox-activity of L preserved upon incorporation in the coordination polymer. Potential barriers of different molecules diffusion through pores were estimated by the means of molecular mechanics. - Highlights: • Porous 1D coordination polymer was synthesized. • Temperature growth led to pores closing due to crystal lattice rearrangement. • Redox-activity of ligand preserved upon incorporation into coordination polymer. • Redox-properties of solid coordination polymer were studied in thin film. • Diffusion barriers were evaluated by molecular mechanics.« less

Multivalent Ion Transport in Polymers via Metal-Ligand Coordination

NASA Astrophysics Data System (ADS)

Sanoja, Gabriel; Schauser, Nicole; Evans, Christopher; Majumdar, Shubhaditya; Segalman, Rachel

Elucidating design rules for multivalent ion conducting polymers is critical for developing novel high-performance materials for electrochemical devices. Herein, we molecularly engineer multivalent ion conducting polymers based on metal-ligand interactions and illustrate that both segmental dynamics and ion coordination kinetics are essential for ion transport through polymers. We present a novel statistical copolymer, poly(ethylene oxide-stat-imidazole glycidyl ether) (i.e., PEO-stat-PIGE), that synergistically combines the structural hierarchy of PEO with the Lewis basicity of tethered imidazole ligands (xIGE = 0.17) required to coordinate a series of transition metal salts containing bis(trifluoromethylsulfonyl)imide anions. Complexes of PEO-stat-PIGE with salts exhibit a nanostructure in which ion-enriched regions alternate with ion-deficient regions, and an ionic conductivity above 10-5 S/cm. Novel normalization schemes that account for ion solvation kinetics are presented to attain a universal scaling relationship for multivalent ion transport in polymers via metal-ligand coordination. AFOSR MURI program under FA9550-12-1.

Toward lanthanide containing coordination polymers and nanomaterials

NASA Astrophysics Data System (ADS)

Greig, Natalie E.

The focus of this thesis is to develop lanthanide (Ln) luminescent materials through the exploration of coordination polymers and nanomaterials. Herein, dimethyl-3,4-furanedicarboxylate acid undergoes hydrolysis under hydrothermal conditions to form coordination polymers with lanthanide ions. The resulting coordination polymers exhibited luminescent properties, with quantum yields and lifetimes for the Eu- and Tb-CP of 1.14±0.31% and 0.387±0.0001 ms, and 3.33±0.82% and 0.769±0.006 ms, respectively. While the incorporation of lanthanides was not achieved in this work, progress toward the production of pure phase InP in the nanoregime has been made, using a low-cost, hydrothermal method. Though SEM and PXRD conflict, it is believed that pure InP particles with a size range of 58-81 nm were successfully synthesized.

Syntheses, structures and selective dye adsorption of five formic-based coordination polymers prepared by in-situ hydrolysis of N, N′-dimethylformamide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Zheng; Meng, Xiang-min; Zhang, Dong-mei

Five functional coordination polymers (formic-based CPs) namely: ([Cu{sub 2}(CHOO){sub 3}(bibp){sub 2}]·CHOO){sub n} (1), ([Co{sub 2}(CHOO){sub 3}(bibp){sub 2}]·NO{sub 3}·H{sub 2}O)n (2), ([Ni{sub 2}(CHOO){sub 3}(bibp){sub 2}]·NO{sub 3}·H{sub 2}O){sub n} (3) [Co(CHOO){sub 2}(bbibp)]{sub n} (4) and [Zn(CHOO){sub 2}(bbibp)]{sub n} (5) (bibp=4,4′-bis(imidazolyl)biphenyl, bbibp=4,4′-bis(benzoimidazo-1-yl)biphenyl) have been successfully hydrothermally synthesized using the in-situ hydrolysis of N, N′-dimethylformamide (DMF) as the source of formate. All of these five polymers were characterized by single-crystal X-ray diffraction, elemental analysis, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analysis. Complexes 1–3 have the similar three-dimensional 3D kag topological framework built from the bibp ligand as the support member betweenmore » the neighboring formic planes. Both complexes 4 and 5 have the similar one-dimensional 1D linear chain which is further assembled into 3D supermolecular structure by C–H…O hydrogen bonds. The dyes adsorption experiments have also been investigated systematically. The results show that complexes 2 and 3 exhibit high selective adsorption ability towards anionic dyes in their aqueous solution. Moreover, complex 2 displays good reversibility in the process of the dyes adsorption-release. Meanwhile, the unusual blocking phenomenon was firstly observed when complex 2 was in MO/OIV aqueous solutions with different concentration.« less

DNA/RNA binding and anticancer/antimicrobial activities of polymer-copper(II) complexes

NASA Astrophysics Data System (ADS)

Lakshmipraba, Jagadeesan; Arunachalam, Sankaralingam; Riyasdeen, Anvarbatcha; Dhivya, Rajakumar; Vignesh, Sivanandham; Akbarsha, Mohammad Abdulkader; James, Rathinam Arthur

2013-05-01

Water soluble polymer-copper(II) complexes with various degrees of coordination in the polymer chain were synthesized and characterized by elemental analysis, IR, UV-visible and EPR spectra. The DNA/RNA binding behavior of these polymer-copper(II) complexes was examined by UV-visible absorption, emission and circular dichroism spectroscopic methods, and cyclic voltammetry techniques. The binding of the polymer-copper(II) complexes with DNA/RNA was mainly through intercalation but some amount of electrostatic interaction was also observed. This binding capacity increased with the degree of coordination of the complexes. The polymer-copper(II) complex having the highest degree of coordination was subjected to analysis of cytotoxic and antimicrobial properties. The cytotoxicity study indicated that the polymer-copper(II) complexes affected the viability of MCF-7 mammary carcinoma cells, and the cells responded to the treatment with mostly through apoptosis although a few cells succumbed to necrosis. The antimicrobial screening showed activity against some human pathogens.

Computer display and manipulation of biological molecules

NASA Technical Reports Server (NTRS)

Coeckelenbergh, Y.; Macelroy, R. D.; Hart, J.; Rein, R.

1978-01-01

This paper describes a computer model that was designed to investigate the conformation of molecules, macromolecules and subsequent complexes. Utilizing an advanced 3-D dynamic computer display system, the model is sufficiently versatile to accommodate a large variety of molecular input and to generate data for multiple purposes such as visual representation of conformational changes, and calculation of conformation and interaction energy. Molecules can be built on the basis of several levels of information. These include the specification of atomic coordinates and connectivities and the grouping of building blocks and duplicated substructures using symmetry rules found in crystals and polymers such as proteins and nucleic acids. Called AIMS (Ames Interactive Molecular modeling System), the model is now being used to study pre-biotic molecular evolution toward life.

Amorphous-amorphous transition in a porous coordination polymer.

PubMed

Ohtsu, Hiroyoshi; Bennett, Thomas D; Kojima, Tatsuhiro; Keen, David A; Niwa, Yasuhiro; Kawano, Masaki

2017-07-04

The amorphous state plays a key role in porous coordination polymer and metal-organic framework phase transitions. We investigate a crystalline-to-amorphous-to-amorphous-to-crystalline (CAAC) phase transition in a Zn based coordination polymer, by X-ray absorption fine structure (XAFS) and X-ray pair distribution function (PDF) analysis. We show that the system shows two distinct amorphous phases upon heating. The first involves a reversible transition to a desolvated form of the original network, followed by an irreversible transition to an intermediate phase which has elongated Zn-I bonds.

Two Zn coordination polymers with meso-helical chains based on mononuclear or dinuclear cluster units

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qin, Ling, E-mail: qinling@hfut.edu.cn; Jiangsu Engineering Technology Research Center of Environmental Cleaning Materials; State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093

2016-07-15

Two zinc coordination polymers {[Zn_2(TPPBDA)(oba)_2]·DMF·1.5H_2O}{sub n} (1), {[Zn(TPPBDA)_1_/_2(tpdc)]·DMF}{sub n} (2) have been synthesized by zinc metal salt, nanosized tetradentate pyridine ligand with flexible or rigid V-shaped carboxylate co-ligands. These complexes were characterized by elemental analyses and X-ray single-crystal diffraction analyses. Compound 1 is a 2-fold interpenetrated 3D framework with [Zn{sub 2}(CO{sub 2}){sub 4}] clusters. Compound 2 can be defined as a five folded interpenetrating bbf topology with mononuclear Zn{sup 2+}. These mononuclear or dinuclear cluster units are linked by mix-ligands, resulting in various degrees of interpenetration. In addition, the photoluminescent properties for TPPBDA ligand under different state and coordination polymersmore » have been investigated in detail. - Graphical abstract: Two zinc coordination polymers have been synthesized by zinc metal salt, nanosized tetradentate pyridine ligand with flexible or rigid V-shaped carboxylate co-ligands. Compound 1 is a 2-fold interpenetrated 3D framework with [Zn{sub 2}(CO{sub 2}){sub 4}] clusters. Compound 2 can be defined as a five folded interpenetrating bbf topology with mononuclear Zn{sup 2+}. In addition, the photoluminescent properties for TPPBDA ligand under different status and coordination polymers have been investigated in detail. Display Omitted - Highlights: • Two Zn coordination polymers based on mononuclear or dinuclear cluster units have been synthesized. • Compound 1 is a 2-fold interpenetrated 3D framework with [Zn{sub 2}(CO{sub 2}){sub 4}] clusters. • Compound 2 is a five folded interpenetrating bbf topology with mononuclear Zn{sup 2+}. • The photoluminescent properties for TPPBDA with different state and two coordination polymers have been investigated.« less

One-Pot Synthesis of Co-Based Coordination Polymer Nanowire for Li-Ion Batteries with Great Capacity and Stable Cycling Stability

NASA Astrophysics Data System (ADS)

Wang, Peng; Lou, Xiaobing; Li, Chao; Hu, Xiaoshi; Yang, Qi; Hu, Bingwen

2018-06-01

Nanowire coordination polymer cobalt-terephthalonitrile (Co-BDCN) was successfully synthesized using a simple solvothermal method and applied as anode material for lithium-ion batteries (LIBs). A reversible capacity of 1132 mAh g-1 was retained after 100 cycles at a rate of 100 mA g-1, which should be one of the best LIBs performances among metal organic frameworks and coordination polymers-based anode materials at such a rate. On the basis of the comprehensive structural and morphology characterizations including fourier transform infrared spectroscopy, 1H NMR, 13C NMR, and scanning electron microscopy, we demonstrated that the great electrochemical performance of the as-synthesized Co-BDCN coordination polymer can be attributed to the synergistic effect of metal centers and organic ligands, as well as the stability of the nanowire morphology during cycling.[Figure not available: see fulltext.

Synthesis, crystal structure and catalytic effect on thermal decomposition of RDX and AP: An energetic coordination polymer [Pb{sub 2}(C{sub 5}H{sub 3}N{sub 5}O{sub 5}){sub 2}(NMP)·NMP]{sub n}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Jin-jian; Yancheng Teachers College, Yancheng 224002; Liu, Zu-Liang, E-mail: liuzl@mail.njust.edu.cn

2013-04-15

An energetic lead(II) coordination polymer based on the ligand ANPyO has been synthesized and its crystal structure has been got. The polymer was characterized by FT-IR spectroscopy, elemental analysis, DSC and TG-DTG technologies. Thermal analysis shows that there are one endothermic process and two exothermic decomposition stages in the temperature range of 50–600 °C with final residues 57.09%. The non-isothermal kinetic has also been studied on the main exothermic decomposition using the Kissinger's and Ozawa–Doyle's methods, the apparent activation energy is calculated as 195.2 KJ/mol. Furthermore, DSC measurements show that the polymer has significant catalytic effect on the thermal decompositionmore » of ammonium perchlorate. - Graphical abstract: An energetic lead(II) coordination polymer of ANPyO has been synthesized, structurally characterized and properties tested. Highlights: ► We have synthesized and characterized an energetic lead(II) coordination polymer. ► We have measured its molecular structure and thermal decomposition. ► It has significant catalytic effect on thermal decomposition of AP.« less

Hand-Ground Nanoscale ZnII -Based Coordination Polymers Derived from NSAIDs: Cell Migration Inhibition of Human Breast Cancer Cells.

PubMed

Paul, Mithun; Sarkar, Koushik; Deb, Jolly; Dastidar, Parthasarathi

2017-04-27

Increased levels of intracellular prostaglandin E 2 (PGE 2 ) have been linked with the unregulated cancer cell migration that often leads to metastasis. Non-steroidal anti-inflammatory drugs (NSAIDs) are known inhibitors of cyclooxygenase (COX) enzymes, which are responsible for the increased PGE 2 concentration in inflamed as well as cancer cells. Here, we demonstrate that NSAID-derived Zn II -based coordination polymers are able to inhibit cell migration of human breast cancer cells. Various NSAIDs were anchored to a series of 1D Zn II coordination polymers through carboxylate-Zn coordination, and these structures were fully characterized by single-crystal X-ray diffraction. Hand grinding in a pestle and mortar resulted in the first reported example of nanoscale coordination polymers that were suitable for biological studies. Two such hand-ground nanoscale coordination polymers NCP1 a and NCP2 a, which contained naproxen (a well-studied NSAID), were successfully internalized by the human breast cancer cells MDA-MB-231, as was evident from cellular imaging by using a fluorescence microscope. They were able to kill the cancer cells (MTT assay) more efficiently than the corresponding mother drug naproxen, and most importantly, they significantly inhibited cancer cell migration thereby displaying anticancer activity. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Two novel two-dimensional copper(II) coordination polymers with 1-(4-aminobenzyl)-1,2,4-triazole: Synthesis, crystal structure, magnetic characterization and absorption of anion pollutants

NASA Astrophysics Data System (ADS)

Zhang, Xin; Wu, Xiang Xia; Guo, Jian-Hua; Huo, Jian-Zhong; Ding, Bin

2017-01-01

In this work a flexible multi-dentate 1-(4-aminobenzyl)-1,2,4-triazole (abtz) ligand has been employed, two novel triazole-Cu(II) coordination polymers {[Cu(abtz)2(Br)2]·(H2O)2}n (1) and {[Cu(abtz)2]·(SiF6)·(H2O)2}n (2) have been isolated under solvo-thermal conditions. 1 is a 2D neutral CuII coordination polymer while 2 is 2D cation micro-porous CuII coordination polymer with the channel dimensionalities of 11.852(1) Å × 11.852(1) Å (metal-metal distances). Variable-temperature magnetic susceptibility data of 1 and 2 have been recorded in the 2-300 K temperature range indicating weak anti-ferromagnetic interactions. Further absorption properties of anion pollutants for 2 also have been investigated. 2 presents the novel example of cationic triazole-copper(II) coordination framework for effectively capturing anion pollutants Cr2O72- in the water solutions and selectively capturing Congo Red in the methanol solutions.

Fluorescent nanoscale zinc(II)-carboxylate coordination polymers for explosive sensing.

PubMed

Zhang, Chengyi; Che, Yanke; Zhang, Zengxing; Yang, Xiaomei; Zang, Ling

2011-02-28

Fluorescent nanoscale coordination polymers with cubic morphology and long range ordered structure were fabricated and exhibited efficient sensing for both nitroaromatic explosive and nitromethane due to large surface area to volume ratio and strong binding affinity to explosive molecules.

Application of geometric algebra for the description of polymer conformations.

PubMed

Chys, Pieter

2008-03-14

In this paper a Clifford algebra-based method is applied to calculate polymer chain conformations. The approach enables the calculation of the position of an atom in space with the knowledge of the bond length (l), valence angle (theta), and rotation angle (phi) of each of the preceding bonds in the chain. Hence, the set of geometrical parameters {l(i),theta(i),phi(i)} yields all the position coordinates p(i) of the main chain atoms. Moreover, the method allows the calculation of side chain conformations and the computation of rotations of chain segments. With these features it is, in principle, possible to generate conformations of any type of chemical structure. This method is proposed as an alternative for the classical approach by matrix algebra. It is more straightforward and its final symbolic representation considerably simpler than that of matrix algebra. Approaches for realistic modeling by means of incorporation of energetic considerations can be combined with it. This article, however, is entirely focused at showing the suitable mathematical framework on which further developments and applications can be built.

Using publically available forest inventory data in climate-based modes of tree species distribution: Examining effects of true versus altered location coordinates

Treesearch

Jacob Gibson; Gretchen Moisen; Tracey Frescino; Thomas C. Edwards

2013-01-01

Species distribution models (SDMs) were built with US Forest Inventory and Analysis (FIA) publicly available plot coordinates, which are altered for plot security purposes, and compared with SDMs built with true plot coordinates. Six species endemic to the western US, including four junipers (Juniperus deppeana var. deppeana, J. monosperma, J. occidentalis, J....

A new redox-active coordination polymer with cobalticinium dicarboxylate.

PubMed

Kondo, Mitsuru; Hayakawa, Yuri; Miyazawa, Makoto; Oyama, Aiko; Unoura, Kei; Kawaguchi, Hiroyuki; Naito, Tetsuyoshi; Maeda, Kenji; Uchida, Fumio

2004-09-20

A new two-dimensional coordination polymer with cobalticinium 1,1'-dicarboxylate (ccdc) incorporated in the framework has been prepared, the ccdc functioning as unique monoanionic dicarboxylate ligands. The compound shows a high redox activity based on the ccdc units. Copyright 2004 American Chemical Society

Syntheses, structures and luminescence of three copper(I) cyanide coordination polymers based on trigonal 1,3,5-tris(1H-imidazol-1-yl)benzene ligand

NASA Astrophysics Data System (ADS)

Shao, Min; Li, Ming-Xing; Lu, Li-Ruo; Zhang, Heng-Hua

2016-09-01

Three Cu(I)-cyanide coordination polymers based on trigonal 1,3,5-tris(1H-imidazol-1-yl)benzene (tib) ligand, namely [Cu3(CN)3(tib)]n (1), [Cu4(CN)4(tib)]n (2), and [Cu2(CN)2(tib)]n (3), have been prepared and characterized by elemental analysis, IR, PXRD, thermogravimetry and single-crystal X-ray diffraction analysis. Complex 1 displays a 3D metal-organic framework with nanosized pores. Complex 2 is a 3D coordination polymer assembled by three μ2-cyanides and a μ3-cyanide with a very short Cu(I)···Cu(I) metal bond(2.5206 Å). Complex 3 is a 2D coordination polymer constructing from 1D Cu(I)-cyanide zigzag chain and bidentate tib spacer. Three Cu(I) complexes are thermally stable up to 250-350 °C. Complexes 1-3 show similar orange emission band at 602 nm originating from LMCT mechanism.

A coordination polymer with unusual structural features from imidazolylbutyric acid and titanium isopropoxide.

PubMed

Czakler, Matthias; Puchberger, Michael; Artner, Christine; Schubert, Ulrich

The coordination polymer [Ti(O i Pr) 3 (OOCCH 2 CH 2 CH 2 C 3 N 2 H 3 )] n was prepared from 4-(imidazol-1-yl)butyric acid and titanium isopropoxide. The structure of the compound is remarkable, as the carboxylate group is coordinated in a chelating manner and no dimerization of the Ti(O i Pr) 3 groups through OR bridges was observed.

Synthesis, structural characterization and antitumor activity of a Ca(II) coordination polymer based on 4-formyl-1,3-benzenedisulfonate-2-furoic acid hydrazide ligands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tai, Xi-Shi, E-mail: taixs@wfu.edu.cn; Wang, Xin

2017-03-15

A new Ca(II) coordination polymer, ([CaL(H{sub 2}O){sub 4}] · (H{sub 2}O){sub 4}){sub n} (L = 4-formyl-1,3-benzenedisulfonate-2-furoic acid hydrazide) has been prepared by one-pot synthesis method. And it was characterized by elemental analysis, IR and thermal analysis. The result of X-ray single-crystal diffraction analysis shows that the Ca(II) complex molecules form one-dimensional chain structure by the bridging oxygen atoms. The anti-tumor activity of L ligand and the Ca(II) coordination polymer has also been studied.

Report of the Polymer Core Course Committee: Inclusion of Polymer Topics into Undergraduate Inorganic Chemistry Courses.

ERIC Educational Resources Information Center

Miller, Norman E.; And Others

1984-01-01

Suggests polymer topics for study in inorganic chemistry courses. Commercial materials (including list of inorganic compounds utilized in polymer industry), anchored metal catalysis, polymers modified or formed by coordination, polysiloxanes, phosphazene or phosphonitrilic halide polymers, and hetergeneous polymerization catalysts are considered.…

Strategies, linkers and coordination polymers for high-performance sorbents

DOEpatents

Matzger, Adam J.; Wong-Foy, Antek G.; Lebel, Oliver

2015-09-15

A linking ligand compound includes three bidentate chemical moieties distributed about a central chemical moiety. Another linking ligand compound includes a bidentate linking ligand and a monodentate chemical moiety. Coordination polymers include a plurality of metal clusters linked together by residues of the linking ligand compounds.

Zinc(II) and Cadmium(II) coordination polymers constructed from phenylenediacetate ligands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sezer, Güneş Günay; Department of Chemistry, Eskişehir Osmangazi University, Eskişehir; Yeşilel, Okan Zafer

ABSTRACT: A series of new coordination polymers {[Zn(μ-opda)(μ-bpa)]·2H_2O}{sub n} (1), [Zn(μ{sub 3}-ppda)(μ-bpa)]{sub n} (2), [Cd(μ{sub 3}-ppda)(μ-bpa)]{sub n} (3), [Cd(μ{sub 3}-mpda)(μ-bpa)]{sub n} (4) and [Cd(μ{sub 3}-mpda)(μ-bipy)]{sub n} (5), (o/m/ppda=1,2/1,3/1,4-phenylenediacetate, bpa=1,2-bi(4-pyridyl)ethane, bipy=4,4′-bipyridine) were synthesized. Their structures were characterized by elemental analysis, IR spectroscopy, single-crystal and powder X-ray diffraction. Furthermore, the effect of metal sources (zinc acetate and zinc oxide) and acidity of the solution on the structure of the coordination polymers was discussed for complexes 1 and 5, respectively. The single-crystal X-ray crystallographic studies revealed that complexes 1, 3, 4 and 5 are uninodal (4)-connected 2D frameworks and display sql topology withmore » the point symbol of (4{sup 4}.6{sup 2}). Complex 2 is 3D coordination polymer and exhibits pcu topology with the point symbol of (4{sup 12}.6{sup 3}). In addition, the luminescent properties and thermal behavior of all complexes were also investigated. - Graphical abstract: Scheme 1. Topologies of Coordination Polymers Reported in This Paper.« less

EXAFS study of some coordination polymers of copper

NASA Astrophysics Data System (ADS)

Deshpande, A. P.

1995-02-01

The EXAFS spectra for (1) azelaic acid bis phenyl hydrazide, (2) azelaic acid bis 2,4 dinitro phenyl hydrazide and (3) sebacic acid bis phenyl hydrazide coordination polymers of copper were obtained using the EXAFS facility of the Daresbury Laboratory. The EXAFS analysis revealed that copper is surrounded by four nitrogen and two oxygen atoms in the first coordination shell, while the second coordination shell consists of two carbon atoms. This information suggests the octahedral geometry for the repeating units of polymeric complexes, in contrast to the square planar geometry previously proposed.

Metal-Organic Polyhedral Core as a Versatile Scaffold for Divergent and Convergent Star Polymer Synthesis.

PubMed

Hosono, Nobuhiko; Gochomori, Mika; Matsuda, Ryotaro; Sato, Hiroshi; Kitagawa, Susumu

2016-05-25

We herein report the divergent and convergent synthesis of coordination star polymers (CSP) by using metal-organic polyhedrons (MOPs) as a multifunctional core. For the divergent route, copper-based great rhombicuboctahedral MOPs decorated with dithiobenzoate or trithioester chain transfer groups at the periphery were designed. Subsequent reversible addition-fragmentation chain transfer (RAFT) polymerization of monomers mediated by the MOPs gave star polymers, in which 24 polymeric arms were grafted from the MOP core. On the other hand, the convergent route provided identical CSP architectures by simple mixing of a macroligand and copper ions. Isophthalic acid-terminated polymers (so-called macroligands) immediately formed the corresponding CSPs through a coordination reaction with copper(II) ions. This convergent route enabled us to obtain miktoarm CSPs with tunable chain compositions through ligand mixing alone. This powerful method allows instant access to a wide variety of multicomponent star polymers that conventionally have required highly skilled and multistep syntheses. MOP-core CSPs are a new class of star polymer that can offer a design strategy for highly processable porous soft materials by using coordination nanocages as a building component.

Tunable emission in lanthanide coordination polymer gels based on a rationally designed blue emissive gelator.

PubMed

Sutar, Papri; Suresh, Venkata M; Maji, Tapas Kumar

2015-06-18

Rational design and synthesis of a new low molecular weight gelator (LMWG) having 9,10-diphenylanthracene core and terminal terpyridine is reported. Tb(III) and Eu(III) ion coordination to a LMWG results in green and pink emissive coordination polymer gels, respectively, with coiled nanofiber morphology. Further, control over stoichiometry of LMWG:Tb(III):Eu(III) leads to yellow and white light emitting bimetallic gels.

Coordination-Supported Imidazolate Networks: Water- and Heat-Stable Mesoporous Polymers for Catalysis

DOE PAGES

Zhang, Pengfei; Yang, Shize; Chisholm, Matthew F.; ...

2017-05-29

The poor water stability of most porous coordination polymers (PCPs) or metal-organic frameworks (MOFs) is widely recognised as a barrier hampering their practical applications. Herein, a facile and scalable route to prepare metal-containing polymers with a good stability in boiling water (100°C, 24 h) and air (up to 390°C) is presented. The bifunctional 1-vinylimidazole (VIm) with both a coordinating site and a polymerizable organic group is introduced as the building block. This core strategy includes the synthesis of a rigid monomer with four VIm branches via a coordination process at room temperature, followed by a radical polymerization. Here we callmore » this material Coordination-supported Imidazolate Networks (CINs). Interestingly, CINs are composed of rich mesopores from 2 to 15 nm, as characterized by low-energy (60 kV) STEM-HAADF images. Especially, the stable CINs illustrate a high turnover frequency (TOF) of 779 h -1 in the catalytic oxidation of phenol with H 2O as the green solvent.« less

Group 10 Metal Benzene-1,2-dithiolate Derivatives in the Synthesis of Coordination Polymers Containing Potassium Countercations.

PubMed

Castillo, Oscar; Delgado, Esther; Gómez-García, Carlos J; Hernández, Diego; Hernández, Elisa; Martín, Avelino; Martínez, José I; Zamora, Félix

2017-10-02

The use of theoretical calculations has allowed us to predict the coordination behavior of dithiolene [M(SC 6 H 4 S) 2 ] 2- (M = Ni, Pd, Pt) entities, giving rise to the first organometallic polymers {[K 2 (μ-H 2 O) 2 ][Ni(SC 6 H 4 S) 2 ]} n and {[K 2 (μ-H 2 O) 2 (thf)] 2 [K 2 (μ-H 2 O) 2 (thf) 2 ][Pd 3 (SC 6 H 4 S) 6 ]} n by one-pot reactions of the corresponding d 10 metal salts, 1,2-benzenedithiolene, and KOH. The polymers are based on σ,π interactions between potassium atoms and [M(SC 6 H 4 S) 2 ] 2- (M = Ni, Pd) entities. In contrast, only σ interactions are observed when the analogous platinum derivative is used instead, yielding the coordination polymer {[K 2 (μ-thf) 2 ][Pt(SC 6 H 4 S) 2 ]} n .

Heterobimetallic coordination polymers involving 3d metal complexes and heavier transition metals cyanometallates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peresypkina, Eugenia V.; Samsonenko, Denis G.; Novosibirsk State University, Novosibirsk 630090

The results of the first steps in the design of coordination polymers based on penta- and heptacyanometallates of heavier d transitions metals are presented. The 2D structure of the coordination polymers: [(Mn(acacen)){sub 2}Ru(NO)(CN){sub 5}]{sub n} and two complexes composed of different cyanorhenates, [Ni(cyclam)]{sub 2}[ReO(OH)(CN){sub 4}](ClO{sub 4}){sub 2}(H{sub 2}O){sub 1.25} and [Cu(cyclam)]{sub 2}[Re(CN){sub 7}](H{sub 2}O){sub 12}, was confirmed by single crystal XRD study, the rhenium oxidation state having been proved by the magnetic measurements. An amorphism of [M(cyclam)]{sub 3}[Re(CN){sub 7}]{sub 2} (M=Ni, Cu) polymers does not allow to define strictly their dimensionality and to model anisotropic magnetic behavior of the compounds.more » However, with high probability a honey-comb like layer structure could be expected for [M(cyclam)]{sub 3}[Re(CN){sub 7}]{sub 2} complexes, studied in this work, because such an arrangement is the most common among the bimetallic assemblies of hexa- and octacyanometallates with a ratio [M(cyclam)]/[M(CN){sub n}]=3/2. For the first time was prepared and fully characterized a precursor (n-Bu{sub 4}N){sub 2}[Ru(NO)(CN){sub 5}], soluble in organic media. - Graphical abstract: The very first results in the design of 2D coordination polymers based on penta- and heptacyanometallates of 4d and5d transitions metals are presented. - Highlights: • Design of coordination polymers based on penta- and heptacyanometallates. • New Ru and Re cyanide based heterobimetallic coordination complexes. • Hydrolysis and ox/red processes involving [Re(CN){sub 7}]{sup 3+} during crystallization. • High magnetic anisotropy of [M(cyclam)]{sub 3}[Re(CN){sub 7}]{sub 2}(H{sub 2}O){sub n}, M=Cu, Ni, complexes.« less

Hybrid materials based on novel 2D lanthanide coordination polymers covalently bonded to amine-modified SBA-15 and MCM-41: assembly, characterization, structural features, thermal and luminescence properties.

PubMed

Wang, Jun; Dou, Wei; Kirillov, Alexander M; Liu, Weisheng; Xu, Cailing; Fang, Ran; Yang, Lizi

2016-11-22

Three novel 2D coordination polymers [Tb 2 (μ 4 -L) 2 (μ-HL)(μ-HCOO)(DEF)] n (Tb-L), [Eu(μ 4 -L)(L)(H 2 O) 2 ] n (Eu-L), and [Nd(μ 4 -L)(L)(H 2 O) 2 ] n (Nd-L) were assembled from the corresponding lanthanide(iii) nitrates and 5 methoxy-(4-benzaldehyde)-1,3-benzenedicarboxylic acid (H 2 L) as a main multifunctional building block bearing carboxylate and aldehyde functional groups, using H 2 O/DEF {DEF = N,N-diethylformamide} as a reaction medium. The obtained coordination polymers were isolated as stable microcrystalline solids and fully characterized by elemental analysis, FT-IR spectroscopy, TGA, BET, PXRD, and single-crystal X-ray diffraction methods. Their structures feature intricate 2D metal-organic networks, which were topologically classified as underlying layers with the 4,6L26 (for Tb-L) or sql (for Eu-L and Nd-L) topologies. Besides, a novel series of mesoporous hybrid materials wherein the Tb-L, Eu-L, or Nd-L coordination polymers are covalently grafted into the amine-functionalized SBA-15-NH 2 or MCM-41-NH 2 matrices (via the formation of Schiff-base groups) was also synthesized and fully characterized. These hybrid materials show high thermal and photoluminescence stability, as well as remarkable chemical resistance to boiling water, and acidic or alkaline medium. Luminescent properties of the parent coordination polymers and derived hybrid materials are investigated in detail, showing that the latter combine the luminescent characteristics (intense green or red emissions and excellent stability) of lanthanide coordination polymers and structural features of ordered mesoporous silica molecular sieves. Moreover, light emitting devices were assembled, by coating the hybrid materials onto the surface of UV-LED bulbs, and showed excellent light emitting properties.

Structural variability in Cu(I) and Ag(I) coordination polymers with a flexible dithione ligand: Synthesis, crystal structure, microbiological and theoretical studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beheshti, Azizolla, E-mail: a.beheshti@scu.ac.ir; Nozarian, Kimia; Babadi, Susan Soleymani

Two new compounds namely [Cu(SCN)(µ-L)]{sub n} (1) and ([Ag (µ{sub 2}-L)](ClO{sub 4})){sub n} (2) have been synthesized at room temperature by one-pot reactions between the 1,1-(1,4-butanediyl)bis(1,3-dihydro-3-methyl-1H-imidazole- 2-thione) (L) and appropriate copper(I) and silver(I) salts. These polymers have been characterized by single crystal X-ray diffraction, XRPD, TGA, elemental analysis, infrared spectroscopy, antibacterial activity and scanning probe microscopy studies. In the crystal structure of 1, copper atoms have a distorted trigonal planar geometry with a CuS{sub 2}N coordination environment. Each of the ligands in the structure of 1 acting as a bidentate S-bridging ligand to form a 1D chain structure. Additionally, themore » adjacent 1D chains are interconnected by the intermolecular C-H…S interactions to create a 2D network structure. In contrast to 1, in the cationic 3D structure of 2 each of the silver atoms exhibits an AgS{sub 4} tetrahedral geometry with 4-membered Ag{sub 2}S{sub 2} rings. In the structure of 2, the flexible ligand adopts two different conformations; gauche-anti-gauche and anti-anti-anti. The antibacterial studies of these polymers showed that polymer 2 is more potent antibacterial agent than 1. Scanning probe microscopy (SPM) study of the treated bacteria was carried out to investigate the structural changes cause by the interactions between the polymers and target bacteria. Theoretical study of polymer 1 investigated by the DFT calculations indicates that observed transitions at 266 nm and 302 nm in the UV–vis spectrum could be attributed to the π→π* and MLCT transitions, respectively. - Graphical abstract: Two new Cu(I) and Ag(I) coordination polymers have been have been synthesized by one-pot reactions. Copper complex has a 2D non-covalent structure, but silver compound is a 3D coordination compound. These compounds have effective antibacterial activity. - Highlights: • Cu(I) and Ag(I) based coordination polymers have different network structures. • Ag(I) polymer has more antibacterial activity than Cu(I) polymer. • DFT calculations of Cu(I) polymer has been investigated. • Cu(I) and Ag(I) polymers can destroy the structure of chromosomal and plasmid DNA.« less

A one-dimensional zinc(II) coordination polymer with a three-dimensional supramolecular architecture incorporating 1-[(1H-benzimidazol-2-yl)methyl]-1H-tetrazole and adipate.

PubMed

Liu, Chun Li; Huang, Qiu Ying; Meng, Xiang Ru

2016-12-01

The synthesis of coordination polymers or metal-organic frameworks (MOFs) has attracted considerable interest owing to the interesting structures and potential applications of these compounds. It is still a challenge to predict the exact structures and compositions of the final products. A new one-dimensional coordination polymer, catena-poly[[[bis{1-[(1H-benzimidazol-2-yl)methyl]-1H-tetrazole-κN 3 }zinc(II)]-μ-hexane-1,6-dicarboxylato-κ 4 O 1 ,O 1' :O 6 ,O 6' ] monohydrate], {[Zn(C 6 H 8 O 4 )(C 9 H 8 N 6 ) 2 ]·H 2 O} n , has been synthesized by the reaction of Zn(Ac) 2 (Ac is acetate) with 1-[(1H-benzimidazol-2-yl)methyl]-1H-tetrazole (bimt) and adipic acid (H 2 adi) at room temperature. In the polymer, each Zn II ion exhibits an irregular octahedral ZnN 2 O 4 coordination geometry and is coordinated by two N atoms from two symmetry-related bimt ligands and four O atoms from two symmetry-related dianionic adipate ligands. Zn II ions are connected by adipate ligands into a one-dimensional chain which runs parallel to the c axis. The bimt ligands coordinate to the Zn II ions in a monodentate mode on both sides of the main chain. In the crystal, the one-dimensional chains are further connected through N-H...O hydrogen bonds, leading to a three-dimensional supramolecular architecture. In addition, the title polymer exhibits fluorescence, with emissions at 334 and 350 nm in the solid state at room temperature.

Highly effective synthesis of a cobalt(ii) metal-organic coordination polymer by using continuous flow chemistry.

PubMed

Gong, Chunhua; Zhang, Junyong; Zeng, Xianghua; Xie, Jingli

2016-12-20

The coordination polymer [Co 2 L 4 (H 2 O) 2 ]·CH 3 CN·H 2 O (HL = (E)-2-[2-(4-chlorophenyl)vinyl]-8-hydroxyquinoline) has been achieved with 95% yield by using an Asia flow synthesis system (chip reactor). Compared with the conventional batch-type methods such as diffusion, reflux and solvothermal reactions, higher yielding reactions carried out in a flow reactor have demonstrated that this technique is a powerful strategy to obtain coordination compounds.

Trace Detection of Metalloporphyrin-Based Coordination Polymer Particles via Modified Surface-Enhanced Raman Scattering Assisted by Surface Metallization.

PubMed

Sun, Yu; Caravella, Alessio

2016-01-01

This study proposed a facile method to detect metalloporphyrin-based coordination polymer particles (Z-CPPs) in aqueous solution by modified surface-enhanced Raman scattering (SERS). The SERS-active particles are photodeposited on the surface of Z-CPPs, offering an enhanced Raman signal for the trace detection of Z-CPPs.

One- and two-dimensional divalent copper coordination polymers based on kinked organodiimine and long flexible aliphatic dicarboxylate ligands

NASA Astrophysics Data System (ADS)

Mallika Krishnan, Subhashree; Supkowski, Ronald M.; LaDuca, Robert L.

2008-11-01

Hydrothermal synthesis under acidic conditions has afforded a pair of divalent copper coordination polymers containing the kinked dipodal tethering organodiimine 4,4'-dipyridylamine (dpa) and flexible long-chain aliphatic dicarboxylate ligands. The new materials were characterized by single crystal X-ray structure determination, infrared spectroscopy, and thermogravimetric analysis. [CuCl(suberate) 0.5(dpa)] ( 1) manifests 1-D ladder-like motifs aggregated into 3-D through hydrogen bonding and copper-mediated supramolecular interactions. Extension of the aliphatic chain within the dicarboxylate ligand by one methylene unit resulted in {[Cu(azelate)(dpa)(H 2O)] · 3H 2O} ( 2), a (4,4) rhomboid grid 2-D coordination polymer encapsulating acyclic water molecule trimers.

The structures and luminescence properties of lanthanide (Ln = Sm, Eu and Tb) metal-organic coordination polymers based on 5-(2-hydroxyethoxy)isophthalate ligand

NASA Astrophysics Data System (ADS)

Wang, Peng; Zhang, Yu-Jie; Qin, Jie; Chen, Yong; Zhao, Ying

2015-03-01

Three unreported isomorphous Ln-containing metal-organic coordination polymeric complexes {LnL(HL)ṡ(H2O)2}n (Ln = Sm (1), Eu (2) and Tb (3), CCDC 971815-971817) were synthesized based on 5-(2-hydroxyethoxy) isophthalic acid (H2L) under hydrothermal conditions. The obtained coordination polymers were characterized by IR, elemental analysis, thermal analysis and X-ray diffraction In solid state, these polymers featured 3-D supramolecular structures constructed by 2-D sheets through H-bonds. Investigation of photoluminescence properties of H2L and 1-3 showed all of them exhibited intense fluorescent emissions in the solid state at room temperature.

C-H...Cl relevant discrepancy on structure, magnetic and electronic conductivity of two mixed-valence Cu{sup I}Cu{sup II} coordination polymers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shi Ling; Yang Ping; School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510631

Two mixed-valence Cu{sup I}Cu{sup II} coordination polymers [Cu{sup I}Cu{sup II}(qdiol)ClL]{sub n} (qdiol{sup 2-}=2,3-dioxyquinoxalinate, L=2,2'-bipyridine, 1; L=1,10-phenanthroline, 2) were obtained in basic ethanolic solution of CuCl{sub 2}, 1,4-dihydro-2,3-quinoxalinedione and L under the solvothermal condition. 1 and 2 are similar in composition, but differ remarkably in structure. The coordination modes of Cu{sup II}, qdiol{sup 2-} and L are identical in both complexes. But the Cu{sup I} ions are two- and three-coordinated, and the Cl{sup -} ions are terminal and bridging, in 1 and 2, respectively, which are relevant to the significantly different C-H...Cl hydrogen bonding pattern of bpy and phen. The temperaturemore » variable magnetic susceptibilities show that 1 is paramagnetic and 2 is weakly antiferromagnetic. The complex impedance spectroscopic studies indicate that both 1 and 2 are semiconductors and 2 is more conducting. - Graphical Abstract: Subtly different C-H...Cl bonding nature leads to diverse coordination modes and supramolecular networks, as well as physical properties of two Cu{sup I}Cu{sup II} coordination polymers with similar compositions. Highlights: > Two new Cu(I)-Cu(II) mixed-valence coordination polymers are obtained. > Environments of Cu(I) and Cl are different caused by C-H...Cl H-bonding. > Supramolecular networks are hence diverse. > Magnetic and semiconducting properties are influenced by the structures.« less

Syntheses, structures and properties of four 3D microporous lanthanide coordination polymers based on 3,5-pyrazoledicarboxylate and oxalate ligands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Juan; Wang, Ji-Jiang; Hu, Huai-Ming, E-mail: ChemHu1@NWU.EDU.CN

2014-04-01

Four three-dimensional lanthanide coordination polymers with reversible structural interconversions, [Ln{sub 2}(Hpdc){sub 2}(C{sub 2}O{sub 4})(H{sub 2}O){sub 4}]{sub n}·2nH{sub 2}O [Ln=Sm (1), Eu (2), Tb (3) and Dy (4)], have been synthesized by hydrothermal reactions of lanthanide nitrates with 3,5-pyrazoledicarboxylic (H{sub 3}pdc) and oxalic acids. It is noteworthy that there is an in situ reaction in 1, in which H{sub 3}pdc was decomposed into (ox){sup 2−} with Cu(II)–Sm(III) synergistic effect under hydrothermal conditions. These compounds are isostructural and crystallized in the monoclinic P2{sub 1}/c space group. The Ln(III) ions are eight-coordinated with dodecahedron coordination geometry. These polyhedra are linked by oxalate groupsmore » to form 1D zigzag chain, which are further connected by 3,5-pyrazoledicarboxylate to extend similar 3D frameworks with channels along c-axis in 1–4. These coordination polymers display the characteristic emission bands of the Ln(III) ions in the solid state and possess good thermal stabilities. - Graphical abstract: Four 3D microporous lanthanide coordination polymers with reversible structural interconversion have been synthesized. They exhibit characteristic emission bands of the lanthanide ions and possess great thermal stability. - Highlights: • Four lanthanide coordination polymers have been hydrothermal synthesized. • There is an in situ reaction in 1 in which H{sub 3}pdc was decomposed into (ox){sup 2−} with the Cu(II)–Sm(III) synergistic effect under hydrothermal conditions. • TGA and XRD studies reveal that upon hydration–dehydration, compounds 1–4 undergo a reversible structural interconversion process through a cooling-heating cycle. • Compounds 1–4 exhibit characteristic lanthanide-centered luminescence.« less

Series of mixed uranyl-lanthanide (Ce, Nd) organic coordination polymers with aromatic polycarboxylates linkers.

PubMed

Mihalcea, Ionut; Volkringer, Christophe; Henry, Natacha; Loiseau, Thierry

2012-09-17

Three series of mixed uranyl-lanthanide (Ce or Nd) carboxylate coordination polymers have been successfully synthesized by means of a hydrothermal route using either conventional or microwave heating methods. These compounds have been prepared from mixtures of uranyl nitrate, lanthanide nitrate together with phthalic acid (1,2), pyromellitic acid (3,4), or mellitic acid (5,6) in aqueous solution. The X-ray diffraction (XRD) single-crystal revealed that the phthalate complex (UO(2))(4)O(2)Ln(H(2)O)(7)(1,2-bdc)(4)·NH(4)·xH(2)O (Ln = Ce(1), Nd(2); x = 1 for 1, x = 0 for 2), is based on the connection of tetranuclear uranyl-centered building blocks linked to discrete monomeric units LnO(2)(H(2)O)(7) via the organic species to generate infinite chains, intercalated by free ammonium cations. The pyromellitate phase (UO(2))(3)Ln(2)(H(2)O)(12)(btec)(3)·5H(2)O (Ce(3), Nd(4)) contains layers of monomeric uranyl-centered hexagonal and pentagonal bipyramids linked via the carboxylate arms of the organic molecules. The three-dimensionality of the structure is ensured by the connection of remaining free carboxylate groups with isolated monomeric units LnO(2)(H(2)O)(7). The network of the third series (UO(2))(2)(OH)Ln(H(2)O)(7)(mel)·5H(2)O (Ce(5), Nd(6)) is built up from dinuclear uranyl units forming layers through connection with the mellitate ligands, which are further linked to each other through discrete monomers LnO(3)(H(2)O)(6). The thermal decomposition of the various coordination complexes led to the formation of mixed uranium-lanthanide oxide, with the fluorite-type structure at 1500 °C (for 1, 2) or 1400 °C for 3-6. Expected U/Ln ratio from the crystal structures were observed for compounds 1-6.

A luminescent zinc(ii) coordination polymer with unusual (3,4,4)-coordinated self-catenated 3D network for selective detection of nitroaromatics and ferric and chromate ions: a versatile luminescent sensor.

PubMed

Zhang, Ya-Qian; Blatov, Vladislav A; Zheng, Tian-Rui; Yang, Chang-Hao; Qian, Lin-Lu; Li, Ke; Li, Bao-Long; Wu, Bing

2018-05-01

A zinc(ii) coordination polymer {[Zn3(mtrb)3(btc)2]·3H2O}n (1) was synthesized and characterized (mtrb = 1,3-bis(1,2,4-triazole-4-ylmethyl)benzene, btc = 1,3,5-benzenetricarboxylate). The polymer 1 shows an unusual (3,4,4)-coordinated self-catenated 3D network with the point symbol of {63}2{62·82·102}{64·82}2. The polymer 1 is the first luminescent sensor for the detection of 2-amino-4-nitrophenol (ANP). The polymer 1 is also a good luminescence sensor for detection of TNP, 2,4-DNP, 4-NP, ANP and 2-NP in MeOH, particularly for TNP. The order of detection efficiency is TNP > 2,4-DNP > 4-NP > ANP > 2-NP. The polymer 1 also exhibits high sensitivity and selectivity as a luminescence sensor for the detection of Fe3+, Cr2O72- and CrO42- in aqueous solution. Our experiments showed that the presence of interfering ions had no significant effect on the sensing of Fe3+, Cr2O72- or CrO42- ions. The detection limits for TNP, ANP, Fe3+, Cr2O72- and CrO42- are 0.22 μM, 4.12 μM, 1.78 μM, 2.83 μM, and 4.52 μM, respectively. The luminescence sensor is stable and can be recycled for detection at least five times. The possible quenching mechanisms are discussed. The polymer 1 is also an effective photocatalyst for degradation of methylene blue (MB) under visible or UV light irradiation.

A Novel Coordination Polymer Constructed by Hetero-Metal Ions and 2,3-Pyridine Dicarboxylic Acid: Synthesis and Structure of [NiNa2(PDC)2(μ-H2O)(H2O)2] n

NASA Astrophysics Data System (ADS)

Dou, Ming-Yu; Lu, Jing

2017-12-01

A novel coordination polymer containing hetero-metal ions, [NiNa2(PDC)2(μ-H2O)(H2O)2] n , where PDC is 2,3-pyridine dicarboxylate ion, has been synthesized. In the structure, the PDC ligand chelates and bridges two Ni(II) and two Na(I) centers. Two kinds of metal centers are connected by μ4-PDC and μ2-H2O to form 2D coordination layers. Hydrogen bonds between coordination water molecules and carboxylate oxygen atoms further link these 2D coordination layers to form 3D supramolecular network.

Synthesis, structure, luminescence and photocatalytic properties of an uranyl-2,5-pyridinedicarboxylate coordination polymer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Si, Zhen-Xiu; Xu, Wei, E-mail: xuwei@nbu.edu.cn; Zheng, Yue-Qing, E-mail: yqzhengmc@163.com

2016-07-15

An uranium coordination polymer, namely [(UO{sub 2}(pydc)(H{sub 2}O)]·H{sub 2}O (1) (H{sub 2}pydc=2,5-pyridinedicarboxylic acid), has been obtained by hydrothermal method and characterized by X-ray single crystal structure determination. Structural analysis reveals that complex 1 exhibits 1D chain coordination polymer, in which UO{sub 2}{sup 2+} ions are bridged by 2,5-pyridinedicarboxylate ligands and the chains are connected into a 3D supramolecular network by O–H···O hydrogen bond interactions and π–π stacking interactions. The photocatalytic properties of 1 for degradation of methylene blue (MB), Rhodamine B (RhB) and methyl orange (MO) under Hg-lamp irradiation have been performed, and the amount of the catalyst as wellmore » as Hg-lamp irradiation with different power on the photodegradation efficiency of MB have been investigated. Elemental analyses, infrared spectroscopy, TG-DTA analyses and luminescence properties were also discussed. - Graphical abstract: Complex 1 exhibits 1D chain coordination polymer in which UO{sub 2}{sup 2+} ions are bridged by 2,5-pyridinedicarboxylate ligand. Photoluminescence studies reveal that complex 1 exhibits characteristic emissions of uranyl centers. The compound is selective to degraded dye and displays good photocatalytic activities for the degradation of MB under Hg-lamp. Display Omitted - Highlights: • Complex 1 exhibits 1D chain coordination polymer. • Complex 1 could degrade methylene blue and Rhodamine B under Hg-lamp irradiation. • Luminescent property of 1 has been studied.« less

Control of hierarchical polymer mechanics with bioinspired metal-coordination dynamics

PubMed Central

Grindy, Scott C.; Learsch, Robert; Mozhdehi, Davoud; Cheng, Jing; Barrett, Devin G.; Guan, Zhibin; Messersmith, Phillip B.; Holten-Andersen, Niels

2015-01-01

In conventional polymer materials, mechanical performance is traditionally engineered via material structure, using motifs such as polymer molecular weight, polymer branching, or copolymer-block design1. Here, by means of a model system of 4-arm poly(ethylene glycol) hydrogels crosslinked with multiple, kinetically distinct dynamic metal-ligand coordinate complexes, we show that polymer materials with decoupled spatial structure and mechanical performance can be designed. By tuning the relative concentration of two types of metal-ligand crosslinks, we demonstrate control over the material’s mechanical hierarchy of energy-dissipating modes under dynamic mechanical loading, and therefore the ability to engineer a priori the viscoelastic properties of these materials by controlling the types of crosslinks rather than by modifying the polymer itself. This strategy to decouple material mechanics from structure may inform the design of soft materials for use in complex mechanical environments. PMID:26322715

Mixing of immiscible polymers using nanoporous coordination templates

NASA Astrophysics Data System (ADS)

Uemura, Takashi; Kaseda, Tetsuya; Sasaki, Yotaro; Inukai, Munehiro; Toriyama, Takaaki; Takahara, Atsushi; Jinnai, Hiroshi; Kitagawa, Susumu

2015-07-01

The establishment of methodologies for the mixing of immiscible substances is highly desirable to facilitate the development of fundamental science and materials technology. Herein we describe a new protocol for the compatibilization of immiscible polymers at the molecular level using porous coordination polymers (PCPs) as removable templates. In this process, the typical immiscible polymer pair of polystyrene (PSt) and poly(methyl methacrylate) (PMMA) was prepared via the successive homopolymerizations of their monomers in a PCP to distribute the polymers inside the PCP particles. Subsequent dissolution of the PCP frameworks in a chelator solution affords a PSt/PMMA blend that is homogeneous in the range of several nanometers. Due to the unusual compatibilization, the thermal properties of the polymer blend are remarkably improved compared with the conventional solvent-cast blend. This method is also applicable to the compatibilization of PSt and polyacrylonitrile, which have very different solubility parameters.

Coordination-Supported Imidazolate Networks: Water- and Heat-Stable Mesoporous Polymers for Catalysis.

PubMed

Zhang, Pengfei; Yang, Shize; Chisholm, Matthew F; Jiang, Xueguang; Huang, Caili; Dai, Sheng

2017-07-26

The poor water stability of most porous coordination polymers (PCPs) or metal-organic frameworks (MOFs) is widely recognized as a barrier hampering their practical applications. Here, a facile and scalable route to prepare metal-containing polymers with a good stability in boiling water (100 °C, 24 h) and air (up to 390 °C) is presented. The bifunctional 1-vinylimidazole (VIm) with a coordinating site and a polymerizable organic group is introduced as the building block. This core strategy includes the synthesis of a rigid monomer with four VIm branches through a coordination process at room temperature, followed by a radical polymerization. We refer to this material as coordination-supported imidazolate networks (CINs). Interestingly, CINs are composed of rich mesopores from 2-15 nm, as characterized by low-energy (60 kV) STEM-HAADF images. In particular, the stable CINs illustrate a high turnover frequency (TOF) of 779 h -1 in the catalytic oxidation of phenol with H 2 O as the green solvent. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Coordination chemistry of 6-thioguanine derivatives with cobalt: toward formation of electrical conductive one-dimensional coordination polymers.

PubMed

Amo-Ochoa, Pilar; Alexandre, Simone S; Hribesh, Samira; Galindo, Miguel A; Castillo, Oscar; Gómez-García, Carlos J; Pike, Andrew R; Soler, José M; Houlton, Andrew; Zamora, Félix; Harrington, Ross W; Clegg, William

2013-05-06

In this work we have synthetized and characterized by X-ray diffraction five cobalt complexes with 6-thioguanine (6-ThioGH), 6-thioguanosine (6-ThioGuoH), or 2'-deoxy-6-thioguanosine (2'-d-6-ThioGuoH) ligands. In all cases, these ligands coordinate to cobalt via N7 and S6 forming a chelate ring. However, independently of reagents ratio, 6-ThioGH provided monodimensional cobalt(II) coordination polymers, in which the 6-ThioG(-) acts as bridging ligand. However, for 2'-d-6-ThioGuoH and 6-ThioGuoH, the structure directing effect of the sugar residue gives rise to mononuclear cobalt complexes which form extensive H-bond interactions to generate 3D supramolecular networks. Furthermore, with 2'-d-6-ThioGuoH the cobalt ion remains in the divalent state, whereas with 6-ThioGuoH oxidation occurs and Co(III) is found. The electrical and magnetic properties of the coordination polymers isolated have been studied and the results discussed with the aid of DFT calculations, in the context of molecular wires.

Syntheses, structures and properties of four 3D microporous lanthanide coordination polymers based on 3,5-pyrazoledicarboxylate and oxalate ligands

NASA Astrophysics Data System (ADS)

Song, Juan; Wang, Ji-Jiang; Hu, Huai-Ming; Wu, Qing-Ran; Xie, Juan; Dong, Fa-Xin; Yang, Meng-Lin; Xue, Gang-Lin

2014-04-01

Four three-dimensional lanthanide coordination polymers with reversible structural interconversions, [Ln2(Hpdc)2(C2O4)(H2O)4]n·2nH2O [Ln=Sm (1), Eu (2), Tb (3) and Dy (4)], have been synthesized by hydrothermal reactions of lanthanide nitrates with 3,5-pyrazoledicarboxylic (H3pdc) and oxalic acids. It is noteworthy that there is an in situ reaction in 1, in which H3pdc was decomposed into (ox)2- with Cu(II)-Sm(III) synergistic effect under hydrothermal conditions. These compounds are isostructural and crystallized in the monoclinic P21/c space group. The Ln(III) ions are eight-coordinated with dodecahedron coordination geometry. These polyhedra are linked by oxalate groups to form 1D zigzag chain, which are further connected by 3,5-pyrazoledicarboxylate to extend similar 3D frameworks with channels along c-axis in 1-4. These coordination polymers display the characteristic emission bands of the Ln(III) ions in the solid state and possess good thermal stabilities.

Novel 3D bismuth-based coordination polymers: Synthesis, structure, and second harmonic generation properties

NASA Astrophysics Data System (ADS)

Wibowo, Arief C.; Smith, Mark D.; Yeon, Jeongho; Halasyamani, P. Shiv; zur Loye, Hans-Conrad

2012-11-01

Two new 3D bismuth containing coordination polymers are reported along with their single crystal structures and SHG properties. Compound 1: Bi2O2(pydc) (pydc=pyridine-2, 5-dicarboxylate), crystallizes in the monoclinic, polar space group, P21 (a=9.6479(9) Å, b=4.2349(4) Å, c=11.9615(11) Å, β=109.587(1)°), which contains Bi2O2 chains that are connected into a 3D structure via the pydc ligands. Compound 2: Bi4Na4(1R3S-cam)8(EtOH)3.1(H2O)3.4 (1R3S cam=1R3S-camphoric acid) crystallizes in the monoclinic, polar space group, P21 (a=19.0855(7) Å, b=13.7706(5) Å, c=19.2429(7) Å, β=90.701(1)°) and is a true 3D coordination polymer. These are two example of SHG compounds prepared using unsymmetric ligands (compound 1) or chiral ligands (compound 2), together with metals that often exhibit stereochemically-active lone pairs, such as Bi3+, a synthetic approach that resulted in polar, non-centrosymmetric, 3D metal-organic coordination polymer.

Sonochemical synthesis and structural characterization of a new nanostructured Co(II) supramolecular coordination polymer with Lewis base sites as a new catalyst for Knoevenagel condensation.

PubMed

Joharian, Monika; Abedi, Sedigheh; Morsali, Ali

2017-11-01

A new Co(II) mixed-ligand coordination supramolecular polymer with composition [Co 2 (ppda)(4-bpdh) 2 (NO 3 ) 2 ] n (1) (where, ppda=p-phenylenediacrylic acid, 4-bpdh=2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene) was synthesized using solvothermal, mechanochemical and sonochemical methods. Compound 1 and the new nanostructure have been characterized by single-crystal X-ray, infrared spectroscopy (IR), powder X-ray diffraction (PXRD) analysis and scanning electron microscopy (SEM). The thermal stability of compound 1 was also studied by thermal gravimetric analysis (TGA). The surface area of these compounds was determined by BET. The single-crystal X-ray data shows a new interesting two-dimensional coordination polymer (CP). In addition, the effect of various sonication concentrations of initial reagents, power of ultrasound irradiation and also the time on the size and morphology of nano-structured coordination polymer 1 were evaluated. Moreover, it has been demonstrated that the nanostructure of the CP1 can be used as a catalyst in Knoevenagel condensation reaction. Copyright © 2017 Elsevier B.V. All rights reserved.

Coordination polymer gels with important environmental and biological applications.

PubMed

Jung, Jong Hwa; Lee, Ji Ha; Silverman, Julian R; John, George

2013-02-07

Coordination Polymer Gels (CPGs) constitute a subset of solid-like metal ion and bridging organic ligand structures (similar to metal-organic frameworks) that form multi-dimensional networks through a trapped solvent as a result of non-covalent interactions. While physical properties of these gels are similar to conventional high molecular weight organic polymer gels, coordination polymer gel systems are often fully reversible and can be assembled and disassembled in the presence of additional energy (heat, sonication, shaking) to give a solution of solvated gelators. Compared to gels resulting from purely organic self-assembled low molecular weight gelators, metal ions incorporated into the fibrilar networks spanning the bulk solvent can impart CPGs with added functionalities. The solid/liquid nature of the gels allows for species to migrate through the gel system and interact with metals, ligands, and the solvent. Chemosensing, catalysis, fluorescence, and drug-delivery applications are some of the many potential uses for these dynamic systems, taking advantage of the metal ion's coordination, the organic polydentate ligand's orientation and functionality, or a combination of these properties. By fine tuning these systems through metal ion and ligand selection and by directing self-assembly with external stimuli the rational synthesis of practical systems can be envisaged.

A coordination polymer based magnetic adsorbent material for hemoglobin isolation from human whole blood, highly selective and recoverable

NASA Astrophysics Data System (ADS)

Zhang, Xiaoxing; Tan, Jipeng; Xu, Xinxin; Shi, Fanian; Li, Guanglu; Yang, Yiqiao

2017-09-01

A composite material has been obtained successfully through the loading of nanoscale coordination polymer on magnetic Fe3O4@SiO2 core-shell particle. In this composite material, coordination polymer nanoparticles distribute uniformly on Fe3O4@SiO2 and these two components are "tied" together firmly with chemical bonds. Adsorption experiments suggest this composite material exhibits very excellent selectivity to hemoglobin. But under the same condition, its adsorption to bovine serum albumin can almost be ignored. This selectivity can be attributed to the existence of hydrophobic interactions between coordination polymer nanoparticle and hemoglobin. For composite material, the hemoglobin adsorption process follows Langmuir model perfectly with high speed. The adsorbed hemoglobin can be eluted easily by sodium dodecyl sulfate stripping reagent with structure and biological activity of hemoglobin keeps well. The composite material was also employed to separate hemoglobin from human whole blood, which receives a very satisfactory result. Furthermore, magnetic measurement reveals ferromagnetic character of this composite material with magnetization saturation 3.56 emu g-1 and this guarantees its excellent magnetic separation performance from the treated solution.

Thermally switchable dielectrics

DOEpatents

Dirk, Shawn M.; Johnson, Ross S.

2013-04-30

Precursor polymers to conjugated polymers, such as poly(phenylene vinylene), poly(poly(thiophene vinylene), poly(aniline vinylene), and poly(pyrrole vinylene), can be used as thermally switchable capacitor dielectrics that fail at a specific temperature due to the non-conjugated precursor polymer irreversibly switching from an insulator to the conjugated polymer, which serves as a bleed resistor. The precursor polymer is a good dielectric until it reaches a specific temperature determined by the stability of the leaving groups. Conjugation of the polymer backbone at high temperature effectively disables the capacitor, providing a `built-in` safety mechanism for electronic devices.

Syntheses, structures and properties of four Cd(II) coordination polymers induced by the pH regulator

NASA Astrophysics Data System (ADS)

Xu, Yun; Ding, Fang; Liu, Dong; Yang, Pei-Pei; Zhu, Li-Li

2018-03-01

Four new coordination polymers [Cd2(CHDC)2(APYZ)(H2O)2](H2O) (1), [Cd(HCHDC)2(APYZ) (H2O)] (2), [Cd2(CHDC)2(PYZ)(H2O)2](H2O) (3), and [Cd(HCHDC)2(PYZ)(H2O)] (4) (H2CHDC = 1,4-cyclohexanedicarboxylic acid, APYZ = 2-aminopyrazine, PYZ = pyrazine) have been synthesized under the hydrothermal conditions by changing the pH regulator and the N-containing ligands. The pH regulator impacted on the degree of deprotonation of the 1,4-cyclohexanedicarboxylic acid ligand and resulted in the formation of the two pairs of different networks. Polymers 1 and 3 crystallize in monoclinic, space group P21/c, exhibit two dimensional 63 net, which further formed three-dimensional supramolecular structure by the Csbnd H⋯O hydrogen bond interactions. While polymers 2 and 4 possess one dimensional chain structures and further link into two dimensional layered supramolecular structures by intermolecular hydrogen bonding interactions. From all three conformers of H2CHDC, e,a-cis is consistently present in the Cd coordination polymers. Furthermore, photoluminescence properties of four polymers are also investigated, the luminescent intensity of polymer 1 (or 2) with amino group in pyrazine is dramatically stronger than that of the similar structure of polymer 3 (or 4) without amino group in pyrazine, the results shown that the presence of the amino group from 2-aminopyrazine play a key role in increasing the luminescence properties.

Synthesis, crystal structures, and luminescent properties of Cd(II) coordination polymers assembled from semi-rigid multi-dentate N-containing ligand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yuan, Gang; Shao, Kui-Zhan; Chen, Lei

2012-12-15

Three new polymers, [Cd(L){sub 2}(H{sub 2}O){sub 2}]{sub n} (1), [Cd{sub 3}(L){sub 2}({mu}{sub 3}-OH){sub 2}({mu}{sub 2}-Cl){sub 2}(H{sub 2}O){sub 2}]{sub n} (2), {l_brace}[Cd{sub 2}(L){sub 2}(nic){sub 2}(H{sub 2}O){sub 2}]{center_dot}H{sub 2}O{r_brace}{sub n} (3) (HL=5-(4-((1H-1,2,4-triazol-1-yl)methyl)phenyl)-1H-tetrazole, Hnic=nicotinic acid) have been prepared and structurally characterized. Compounds 1 and 2 display 2D monomolecular layers built by the inter-linking single helical chains and L{sup -} ligands connecting chain-like [Cd({mu}{sub 3}-OH)({mu}{sub 2}-Cl)]{sub n} secondary building units, respectively. Compound 3 is constructed from the mixed ligands and possesses a (3,4)-connected framework with (4{center_dot}8{sup 2})(4{center_dot}8{sup 2}{center_dot}10{sup 3}) topology. Moreover, the fluorescent properties of HL ligand and compounds 1-3 are also been investigated.more » - Graphical abstract: Three new coordination polymers based on the semi-rigid multidentate N-donor ligand have been successfully synthesized by hydrothermal reaction. Complexes 1 and 2 exhibit the 2D layers formed by inter-linking single helices and L{sup -} anions bridging 1D chain-like SBUs, respectively. Complex 3 is buit by L{sup -} and assistant nic{sup -} ligands connecting metal centers and possesses a (3,4)-connected framework with (4 Multiplication-Sign 8{sup 2})(4 Multiplication-Sign 8{sup 2} Multiplication-Sign 10{sup 3}) topology. Moreover, these complexes display fluorescent properties indicating that they may have potential applications as optical materials. Highlights: Black-Right-Pointing-Pointer Three Cd-compounds were prepared from semi-rigid HL ligand with different N-containing groups. Black-Right-Pointing-Pointer They exhibit diverse structures from 2D monomolecular layer to 3D covalent framework. Black-Right-Pointing-Pointer The HL ligands displayed various coordination modes under different reaction conditions. Black-Right-Pointing-Pointer These compounds exhibit good luminescent properties.« less

Metal Coordination Stoichiometry Controlled Formation of Linear and Hyperbranched Supramolecular Polymers.

PubMed

Lin, Cuiling; Xu, Luonan; Huang, Libo; Chen, Jia; Liu, Yuanyuan; Ma, Yifan; Ye, Feixiang; Qiu, Huayu; He, Tian; Yin, Shouchun

2016-09-01

Controlling the topologies of polymers is a hot topic in polymer chemistry because the physical and/or chemical properties of polymers are determined (at least partially) by their topologies. This study exploits the host-guest interactions between dibenzo-24-crown-8 and secondary ammonium salts and metal coordination interactions between 2,6-bis(benzimidazolyl)-pyridine units with metal ions (Zn(II) and/or Eu(III) ) as orthogonal non-covalent interactions to prepare supramolecular polymers. By changing the ratios of the metal ion additives (Zn(NO3 )2 and Eu(NO3 )3 ) linkers to join the host-guest dimeric complex, the linear supramolecular polymers (100 mol% Zn(NO3 )2 per ligand) and hyperbranched supramolecular polymers (97 mol% Zn(NO3 )2 and 3 mol% Eu(NO3 )3 per ligand) are separately and successfully constructed. This approach not only expands topological control over polymeric systems, but also paves the way for the functionalization of smart and adaptive materials. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

N-(sulfoethyl) iminodiacetic acid-based lanthanide coordination polymers: Synthesis, magnetism and quantum Monte Carlo studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhuang Guilin, E-mail: glzhuang@zjut.edu.cn; Chen Wulin; Zheng Jun

2012-08-15

A series of lanthanide coordination polymers have been obtained through the hydrothermal reaction of N-(sulfoethyl) iminodiacetic acid (H{sub 3}SIDA) and Ln(NO{sub 3}){sub 3} (Ln=La, 1; Pr, 2; Nd, 3; Gd, 4). Crystal structure analysis exhibits that lanthanide ions affect the coordination number, bond length and dimension of compounds 1-4, which reveal that their structure diversity can be attributed to the effect of lanthanide contraction. Furthermore, the combination of magnetic measure with quantum Monte Carlo(QMC) studies exhibits that the coupling parameters between two adjacent Gd{sup 3+} ions for anti-anti and syn-anti carboxylate bridges are -1.0 Multiplication-Sign 10{sup -3} and -5.0 Multiplication-Signmore » 10{sup -3} cm{sup -1}, respectively, which reveals weak antiferromagnetic interaction in 4. - Graphical abstract: Four lanthanide coordination polymers with N-(sulfoethyl) iminodiacetic acid were obtained under hydrothermal condition and reveal the weak antiferromagnetic coupling between two Gd{sup 3+} ions by Quantum Monte Carlo studies. Highlights: Black-Right-Pointing-Pointer Four lanthanide coordination polymers of H{sub 3}SIDA ligand were obtained. Black-Right-Pointing-Pointer Lanthanide ions play an important role in their structural diversity. Black-Right-Pointing-Pointer Magnetic measure exhibits that compound 4 features antiferromagnetic property. Black-Right-Pointing-Pointer Quantum Monte Carlo studies reveal the coupling parameters of two Gd{sup 3+} ions.« less

Molecular modeling studies of interactions between sodium polyacrylate polymer and calcite surface

NASA Astrophysics Data System (ADS)

Ylikantola, A.; Linnanto, J.; Knuutinen, J.; Oravilahti, A.; Toivakka, M.

2013-07-01

The interactions between calcite pigment and sodium polyacrylate dispersing agent, widely used in papermaking as paper coating components, were investigated using classical force field and quantum chemical approaches. The objective was to understand interactions between the calcite surface and sodium polyacrylate polymer at 300 K using molecular dynamics simulations. A quantum mechanical ab initio Hartree-Fock method was also used to obtain detailed information about the sodium polyacrylate polymer structure. The effect of water molecules (moisture) on the interactions was also examined. Calculations showed that molecular weight, branching and the orientation of sodium polyacrylate polymers influence the interactions between the calcite surface and the polymer. The force field applied, and also water molecules, were found to have an impact on all systems studied. Ab initio Hartree-Fock calculations indicated that there are two types of coordination between sodium atoms and carboxylate groups of the sodium polyacrylate polymer, inter- and intra-carboxylate group coordination. In addition, ab initio Hartree-Fock calculations of the structure of the sodium polyacrylate polymer produced important information regarding interactions between the polymers and carboxylated styrene-butadiene latex particles.

Syntheses, structures and luminescent properties of lanthanide coordination polymers assembled from imidazophenanthroline derivative and oxalate ligands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Hui; Sun, Xiao-Xia; Hu, Huai-Ming, E-mail: ChemHu1@NWU.EDU.CN

2017-01-15

Nine new lanthanide coordination polymers, namely, [Ln(Hsfpip)(ox){sub 0.5}(H{sub 2}O)]{sub n}·2n(H{sub 2}O) ((Ln=Eu (1), Tb (2), Dy (3), Ho (4), Er (5), Yb (6), Y(7)), [Ln(H{sub 2}sfpip)(ox)(H{sub 2}O){sub 4}]{sub n}·2n(H{sub 2}O) (Ln=Nd (8) Sm (9)), [H{sub 2}ox=oxalic acid, H{sub 3}sfpip=2-(2,4-disulfophenyl)imidazo(4,5-f)(1,10)-phenanthroline] have been synthesized under hydrothermal conditions and characterized by IR spectra, elemental analysis, powder X-ray diffraction and single crystal X-ray diffraction. When sodium oxalate is added, the reactions of lanthanide ions with H{sub 3}sfpip resulted in two types of structures. Compounds 1–7 are obtained at pH 5.0 and exhibit 3D tfz-d networks with ox{sup 2−} anions as linkers to bridge themore » adjacent layers. Compounds 8–9 are obtained at pH 2.0, and display a 1D chain which is further extended to a 3D supramolecular framework through intermolecular hydrogen bonds and π-π interactions. The structural variation from compounds 1–7 to 8–9 can attribute to the pH effect on construction of lanthanide coordination polymers. Moreover, the thermal stabilities and luminescence properties of 1–9 were also investigated. - Graphical abstract: Nine new lanthanide coordination polymers have been synthesized under hydrothermal conditions. Compounds 1–7 exhibit a 3D tfz-d network. Compounds 8–9 display a 1D chain structure. The structural variation from compounds 1–7 to 8–9 can attribute to the pH effect on construction of lanthanide coordination polymers. - Highlights: • Nine lanthanide coordination polymers were prepared under hydrothermal conditions. • Their crystal structures have been determined. • The luminescence and thermal stabilities were studied in the solid state.« less

Dimensional modulation and magnetic properties of triazole- and bis(triazole)-based copper(II) coordination polymers tuned by aromatic polycarboxylates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Ju-Wen; Zhao, Wei; Lu, Qi-Lin

2014-04-01

Five new metal–organic coordination polymers ([Cu{sub 3}(μ{sub 2}-OH){sub 2}(atrz){sub 2}(nph){sub 2}(H{sub 2}O){sub 2}]·2H{sub 2}O){sub n} (1), ([Cu{sub 2}(μ{sub 3}-OH)(atrz)(1,2,4-btc)]·2H{sub 2}O){sub n} (2), ([Cu{sub 2}(μ{sub 3}-OH)(atrz)(1,2,4-btc)(H{sub 2}O)]·H{sub 2}O){sub n} (3), [Cu(dth){sub 0.5}(nph)(H{sub 2}O)]{sub n} (4) and [Cu(dth)(Hnip){sub 2}]{sub n} (5) [atrz=4-amino-1,2,4-triazole, dth=N,N'-di(4H-1,2,4-triazole)hexanamide, H{sub 2}nph=3-nitrophthalic acid, 1,2,4-H{sub 3}btc=1,2,4-benzenetricarboxylic acid and H{sub 2}nip=5-nitroisophthalic acid] were hydrothermally synthesized and structurally characterized. Polymer 1 shows a one-dimensional (1D) chain. Polymers 2 and 3 exhibit similar tetranuclear Cu{sup II}{sub 4} cluster-based three-dimensional (3D) frameworks with the same components. Polymer 4 possesses a 3D framework with a 4{sup 12}·6{sup 3}-pcu topology. Polymer 5 displays a 3D frameworkmore » with a 4{sup 4}·6{sup 10}·8-mab topology. The magnetic properties of 1–4 were investigated. - Graphical abstract: Five triazole-based copper(II) polymers modulated by polycarboxylates were synthesized. Bis-triazole-bis-amide ligand and polycarboxylates play important roles in tuning dimensionality of polymers. Magnetic properties of polymers were investigated. - Highlights: • Five triazole- and bis(triazole)-based copper(II) coordination polymers tuned by aromatic polycarboxylates were obtained. • The aromatic polycarboxylates have an important influence on the dimensionality of five polymers. • The magnetic properties of four polymers were investigated.« less

Lanthanide coordination polymers: Synthesis, diverse structure and luminescence properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Xue-Qin, E-mail: songxq@mail.lzjtu.cn; Lei, Yao-Kun; Wang, Xiao-Run

2014-10-15

The new semirigid exo-bidentate ligand incorporating furfurysalicylamide terminal groups, namely, 1,4-bis([(2′-furfurylaminoformyl)phenoxyl]methyl)-2,5-bismethylbenzene (L) was synthesized and used as building blocks for constructing lanthanide coordination polymers with luminescent properties. The series of lanthanide nitrate complexes have been characterized by elemental analysis, IR spectroscopy, and X-ray diffraction analysis. The semirigid ligand L, as a bridging ligand, reacts with lanthanide nitrates forming three distinct structure types: chiral noninterpenetrated two-dimensional (2D) honeycomblike (6,3) (hcb, Schläfli symbol 6{sup 3}, vertex symbol 6 6 6) topological network as type I, 1D zigzag chain as type II and 1D trapezoid ladder-like chain as type III. The structural diversitiesmore » indicate that lanthanide contraction effect played significant roles in the structural self-assembled process. The luminescent properties of Eu{sup III}, Tb{sup III} and Dy{sup III} complexes are discussed in detail. Due to the good match between the lowest triplet state of the ligand and the resonant energy level of the lanthanide ion, the lanthanide ions in Eu{sup III}, Tb{sup III} and Dy{sup III} complexes can be efficiently sensitized by the ligand. - Graphical abstract: We present herein six lanthanide coordination polymers of a new semirigid exo-bidentate ligand which not only display diverse structures but also possess strong luminescence properties. - Highlights: • We present lanthanide coordination polymers of a new semirigid exo-bidentate ligand. • The lanthanide coordination polymers exhibit diverse structures. • The luminescent properties of Tb{sup III}, Eu{sup III} and Dy{sup III} complexes are discussed in detail.« less

New Secondary Batteries Using Electronically Conductive Polymer Cathodes

NASA Technical Reports Server (NTRS)

Martin, Charles R.; White, Ralph E.

1991-01-01

A Li/Polypyrrole secondary battery was designed and built, and the effect of controlling the morphology of the polymer on enhancement of counterion diffusion in the polymer phase was explored. The experimental work was done at Colorado State University, while the mathematical modeling of the battery was done at Texas A and M University. Manuscripts and publications resulting from the project are listed.

An in situ tribometer for measuring friction and wear of polymers in a high pressure hydrogen environment

NASA Astrophysics Data System (ADS)

Duranty, Edward R.; Roosendaal, Timothy J.; Pitman, Stan G.; Tucker, Joseph C.; Owsley, Stanley L.; Suter, Jonathan D.; Alvine, Kyle J.

2017-09-01

High pressure hydrogen effects on the friction and wear of polymers are of importance to myriad applications. Of special concern are those used in the infrastructure for hydrogen vehicle refueling stations, including compressor sliding seals, valves, and actuators. While much is known about potentially damaging embrittlement effects of hydrogen on metals, relatively little is known about the effects of high pressure hydrogen on polymers. However, based on the limited results that are published in the literature, polymers also apparently exhibit compatibility issues with hydrogen. An additional study is needed to elucidate these effects to avoid incompatibilities either through design or material selection. As part of this effort, we present here in situ high pressure hydrogen studies of the friction and wear on example polymers. To this end, we have built and demonstrated a custom-built pin-on-flat linear reciprocating tribometer and demonstrated its use with in situ studies of friction and wear behavior of nitrile butadiene rubber polymer samples in 28 MPa hydrogen. Tribology results indicate that friction and wear is increased in high pressure hydrogen as compared both with values measured in high pressure argon and ambient air conditions.

Two-fold interpenetrating btc based cobaltous coordination polymer: A promising catalyst for solvent free oxidation of 1-hexene

NASA Astrophysics Data System (ADS)

Bora, Sanchay J.; Paul, Rima; Nandi, Mithun; Bhattacharyya, Pradip K.

2017-12-01

This work describes the synthesis of a new 2-D coordination polymer (CP), [Co3(btc)2(dmp)8]n (btc = 1,3,5-benzenetricarboxylate and dmp = 3,5-dimethylpyrazole) and its catalytic activity towards the oxidation reaction of 1-hexene to form oxygenated compounds under solvent free condition. Structural analysis reveals that Co(II) cations in this polymeric compound are linked by btc3- anions with alternate tetrahedral/octahedral coordination forming a two-fold interpenetrated 3-connected hcb underlying net. Electronic spectrum of the cobaltous polymer has been calculated using TDDFT/B3LYP method for making the appropriate assignments of electronic transitions. Catalytic results show good conversions of the starting material to oxygenated products with high selectivities for 1,2-epoxyhexane and 1-hexanal.

Polymer Directed Self-Assembly of pH-Responsive Antioxidant Nanoparticles

PubMed Central

Tang, Christina; Amin, Devang; Messersmith, Phillip B.; Anthony, John E.; Prud’homme, Robert K.

2015-01-01

We have developed pH-responsive, multifunctional nanoparticles based on encapsulation of an antioxidant, tannic acid (TA), using Flash NanoPrecipitation, a polymer directed self-assembly method. Formation of insoluble coordination complexes of tannic acid and iron during mixing drives nanoparticle assembly. Tuning the core material to polymer ratio, the size of the nanoparticles can be readily tuned between 50 and 265 nm. The resulting nanoparticle is pH-responsive, i.e. stable at pH 7.4 and soluble under acidic conditions due to the nature of the coordination complex. Further, the coordination complex can be coprecipitated with other hydrophobic materials such as therapeutics or imaging agents. For example, coprecipitation with a hydrophobic fluorescent dye creates fluorescent nanoparticles. In vitro, the nanoparticles have low cytotoxicity show antioxidant activity. Therefore, these particles may facilitate intracellular delivery of antioxidants. PMID:25760226

Highly efficient temperature-dependent chiral separation with a nucleotide-based coordination polymer.

PubMed

Bruno, Rosaria; Marino, Nadia; Bartella, Lucia; Di Donna, Leonardo; De Munno, Giovanni; Pardo, Emilio; Armentano, Donatella

2018-06-05

We report a new chiral coordination polymer, prepared from the cytidine 5'-monophosphate (CMP) nucleotide, capable of separating efficiently (enantiomeric excess of ca. 100%) racemic mixtures of l- and d-Asp in a temperature-dependent manner. The crystal structure of the host-guest adsorbate, with the d-Asp guest molecules loaded within its channels, could be solved allowing a direct visualization of the chiral recognition process.

Nanometrization of Lanthanide-Based Coordination Polymers.

PubMed

Neaime, Chrystelle; Daiguebonne, Carole; Calvez, Guillaume; Freslon, Stéphane; Bernot, Kevin; Grasset, Fabien; Cordier, Stéphane; Guillou, Olivier

2015-11-23

Heteronuclear lanthanide-based coordination polymers are microcrystalline powders, the luminescence properties of which can be precisely tuned by judicious choice of the rare-earth ions. In this study, we demonstrate that such materials can also be obtained as stable solutions of nanoparticles in non-toxic polyols. Bulk powders of the formula [Ln2-2x Ln'2x (bdc)3 ⋅4 H2 O]∞ (where H2 bdc denotes 1,4-benzene-dicarboxylic acid, 0≤x≤1, and Ln and Ln' denote lanthanide ions of the series La to Tm plus Y) afford nanoparticles that have been characterized by dynamic light-scattering (DLS) and transmission electron microscopy (TEM) measurements. Their luminescence properties are similar to those of the bulk materials. Stabilities versus time and versus dilution with another solvent have been studied. This study has revealed that it is possible to tune the size of the nanoparticles. This process offers a reliable means of synthesizing suspensions of nanoparticles with tunable luminescence properties and tunable size distributions in a green solvent (glycerol). The process is also extendable to other coordination polymers and other solvents (ethylene glycol, for example). It constitutes a new route for the facile solubilization of lanthanide-based coordination polymers. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Homochiral coordination polymers with helixes and metal clusters based on lactate derivatives

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Zhong-Xuan, E-mail: xuzhongxuan4201@163.com; Ma, Yu-Lu; Lv, Guo-ling

2017-05-15

Utilizing the lactic acid derivatives (R)-4-(1-carboxyethoxy)benzoic acid (denoted: (R)-H{sub 2}CBA) and (S)-4-(1-carboxyethoxy)benzoic acid (denoted: (S)-H{sub 2}CBA)as chiral linkers to self-assemble with 4, 4′-bipyridine (denoted: BIP) and Cd(II) ions, a couple of three-dimensional homochiral coordination polymers, namely [Cd{sub 3}((R)-CBA){sub 3} (BIP){sub 2}(H{sub 2}O)]·xGuest (1-D) and [Cd{sub 3}((S)-CBA){sub 3}(BIP){sub 2}(H{sub 2}O)]·xGuest (1-L), have been synthesized under solvothermal reaction condition. Single crystal X-ray diffraction analysis reveals the two complexes contain single helical chains based on enantiopure ligands and cadmium clusters. Moreover, some physical characteristics such as PXRD, thermal stability, solid-state circular dichroism (CD) and luminescent were also investigated. - Graphical abstract: Utilizing enantiomericmore » lactic acid derivatives (R)-H{sub 2}CBA and (S)-H{sub 2}CBA to assemble with Cd{sup 2+} ions and ancillary BIP ligands, a couple of 3D homochiral coordination polymers with metal clusters and helical chains have been prepared by hydrothermal reaction. - Highlights: • Chiral lactic acid derivative. • Enantiomeric coordination polymer. • Helical chain. • Trinuclear cadmium cluster.« less

Research notes : polymer modified emulsions for chip seals.

DOT National Transportation Integrated Search

1991-12-01

The Research Unit is conducting a study of chip seal emulsions using asphalts containing polymers on test sections that were built in 1987 on Oregon Route 22 near Stayton in Marion County. A commonly used emulsion in the 1987 OSHD Specifications for ...

Assembly of 4-, 6- and 8-connected Cd(II) pseudo-polymorphic coordination polymers: Synthesis, solvent-dependent structural variation and properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Zhao-Hao; Xue, Li-Ping, E-mail: lpxue@163.com; Miao, Shao-Bin

2016-08-15

The reaction of Cd(NO{sub 3}){sub 2}·4H{sub 2}O, 2,5-thiophenedicarboxylic acid (H{sub 2}tdc) and 1,2-bis(imidazol-1′-yl)methane (bimm) by modulating solvent systems yielded three highly connected pseudo-polymorphic coordination polymers based on different dinuclear [Cd{sub 2}(CO{sub 2}){sub 2}] subunits bridged by carboxylate groups. Single crystal structural analyses reveal structural variation from 4-connected 2D sql layer, 6-connected 2-fold interpenetrated 3D pcu to 8-connected 3D bcu-type network in compounds 1–3. The structural dissimilarity in the structures dependent on the coordination environments of Cd(II) ions and linking modes of mixed ligand influenced by different solvent systems during the synthesis process. Moreover, thermogravimetric and photoluminescence behaviors of 1–3 weremore » also investigated for the first time, and all the complexes emit blue luminescence in the solid state. - Graphical abstract: Key Topic. Different solvent systems modulated three Cd(II) pseudo-polymorphic coordination polymers based on thiophene-2,5-dicarboxylate and 1,2-bis(imidazol-1′-yl)methane mixed ligands. Display Omitted - Highlights: • Three solvent-dependent Cd(II) pseudo-polymorphic coordination polymers have been synthesized. • Structural variation from 4-connected 2D layer, 6-connected 2-fold interpenetrated 3D net to 8-connected 3D net. • All complexes emit blue luminescence.« less

Coordination Polymer: Synthesis, Spectral Characterization and Thermal Behaviour of Starch-Urea Based Biodegradable Polymer and Its Polymer Metal Complexes

PubMed Central

Malik, Ashraf; Parveen, Shadma; Ahamad, Tansir; Alshehri, Saad M.; Singh, Prabal Kumar; Nishat, Nahid

2010-01-01

A starch-urea-based biodegradable coordination polymer modified by transition metal Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) was prepared by polycondensation of starch and urea. All the synthesized polymeric compounds were characterized by Fourier transform-infrared spectroscopy (FT-IR), 1H-NMR spectroscopy, 13C-NMR spectroscopy, UV-visible spectra, magnetic moment measurements, differential scanning calorimeter (DSC), and thermogravimetric analysis (TGA). The results of electronic spectra and magnetic moment measurements indicate that Mn(II), Co(II), and Ni(II) complexes show octahedral geometry, while Cu(II) and Zn(II) complexes show square planar and tetrahedral geometry, respectively. The thermogravimetric analysis revealed that all the polymeric metal complexes are more thermally stable than the parental ligand. In addition, biodegradable studies of all the polymeric compounds were also carried out through ASTM standards of biodegradable polymers by CO2 evolution method. PMID:20414461

A new Pb{sup II}(ethylenediaminetetraacetate) coordination polymer with a two-dimensional layer structure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, D., E-mail: iamzd@hpu.edu.cn; Zhang, R. H.; Li, F. F.

2016-12-15

A new Pb{sup II}−edta{sup 4–} coordination polymer, Pb{sub 2}(edta)(H{sub 2}O){sub 0.76} (edta{sup 4–} = ethylenediaminetetraacetate) was synthesized under hydrothermal condition. Single crystal X-ray analysis reveals that it represents a novel two-dimensional (2D) Pb{sup 2+}–edta{sup 4–} layer structure with a (4,8{sup 2})-topology. Each edta{sup 4–} ligand employs its four carboxylate O and two N atoms to chelate one Pb{sup II} atom (hexa-coordinated) and connects five Pb{sup II} atoms (ennea-coordinated) via its four carboxylate groups to form 2D layer framework. Adjacent layers are packed into the overall structure through vander Waals interactions.

Dynamic Coordination of Eu-Iminodiacetate to Control Fluorochromic Response of Polymer Hydrogels to Multistimuli.

PubMed

Weng, Gengsheng; Thanneeru, Srinivas; He, Jie

2018-03-01

New fluorochromic materials that reversibly change their emission properties in response to their environment are of interest for the development of sensors and light-emitting materials. A new design of Eu-containing polymer hydrogels showing fast self-healing and tunable fluorochromic properties in response to five different stimuli, including pH, temperature, metal ions, sonication, and force, is reported. The polymer hydrogels are fabricated using Eu-iminodiacetate (IDA) coordination in a hydrophilic poly(N,N-dimethylacrylamide) matrix. Dynamic metal-ligand coordination allows reversible formation and disruption of hydrogel networks under various stimuli which makes hydrogels self-healable and injectable. Such hydrogels show interesting switchable ON/OFF luminescence along with the sol-gel transition through the reversible formation and dissociation of Eu-IDA complexes upon various stimuli. It is demonstrated that Eu-containing hydrogels display fast and reversible mechanochromic response as well in hydrogels having interpenetrating polymer network. Those multistimuli responsive fluorochromic hydrogels illustrate a new pathway to make smart optical materials, particularly for biological sensors where multistimuli response is required. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Solvent induced synthesis, structure and properties of coordination polymers based on 5-hydroxyisophthalic acid as linker and 1,10-phenanthroline as auxiliary ligand

NASA Astrophysics Data System (ADS)

Kariem, Mukaddus; Yawer, Mohd; Sheikh, Haq Nawaz

2015-11-01

Three new coordination polymers [Mn(hip)(phen) (H2O)]n (1), [Co(hip)(phen) (H2O)]n (2), and [Cd(hip) (phen) (H2O)]n (3) (H2hip=5-hydroxyisophthalic acid; phen=1,10-phenanthroline) have been synthesized by solvo-hydrothermal method using diethyl formamide-water (DEF-H2O) as solvent system. Single-crystal X-ray diffraction analysis reveals that all three coordination polymers 1, 2 and 3 crystallize in monoclinic space group P2/n. Metal ions are inter-connected by hydroxyisophthalate anions forming zig-zag 1D chain. 1D chains are further inter-connected by hydrogen bonding and π-π stacking interactions leading to 3D supramolecular architecture. Hydrogen-bonding and π-π stacking provide thermal stability to polymers. Compounds 1 and 2 are paramagnetic at room temperature and variable temperature magnetic moment measurements revealed weak ferromagnetic interactions between metal ions at low temperature. Compound 3 exhibits excellent photoluminescence with large Stokes shift.

Prediction of Material Properties of Nanostructured Polymer Composites Using Atomistic Simulations

NASA Technical Reports Server (NTRS)

Hinkley, J.A.; Clancy, T.C.; Frankland, S.J.V.

2009-01-01

Atomistic models of epoxy polymers were built in order to assess the effect of structure at the nanometer scale on the resulting bulk properties such as elastic modulus and thermal conductivity. Atomistic models of both bulk polymer and carbon nanotube polymer composites were built. For the bulk models, the effect of moisture content and temperature on the resulting elastic constants was calculated. A relatively consistent decrease in modulus was seen with increasing temperature. The dependence of modulus on moisture content was less consistent. This behavior was seen for two different epoxy systems, one containing a difunctional epoxy molecule and the other a tetrafunctional epoxy molecule. Both epoxy structures were crosslinked with diamine curing agents. Multifunctional properties were calculated with the nanocomposite models. Molecular dynamics simulation was used to estimate the interfacial thermal (Kapitza) resistance between the carbon nanotube and the surrounding epoxy matrix. These estimated values were used in a multiscale model in order to predict the thermal conductivity of a nanocomposite as a function of the nanometer scaled molecular structure.

One-dimensional Cu(II) coordination polymers containing C2h-symmetric 1,1':4',1''-terphenyl-3,3'-dicarboxylate linkers.

PubMed

Kim, Hyun Chul; Gu, Ja Min; Huh, Seong; Yo, Chul Hyun; Kim, Youngmee

2015-10-01

Two new one-dimensional Cu(II) coordination polymers (CPs) containing the C2h-symmetric terphenyl-based dicarboxylate linker 1,1':4',1''-terphenyl-3,3'-dicarboxylate (3,3'-TPDC), namely catena-poly[[bis(dimethylamine-κN)copper(II)]-μ-1,1':4',1''-terphenyl-3,3'-dicarboxylato-κ(4)O,O':O'':O'''] monohydrate], {[Cu(C20H12O4)(C2H7N)2]·H2O}n, (I), and catena-poly[[aquabis(dimethylamine-κN)copper(II)]-μ-1,1':4',1''-terphenyl-3,3'-dicarboxylato-κ(2)O(3):O(3')] monohydrate], {[Cu(C20H12O4)(C2H7N)2(H2O)]·H2O}n, (II), were both obtained from two different methods of preparation: one reaction was performed in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) as a potential pillar ligand and the other was carried out in the absence of the DABCO pillar. Both reactions afforded crystals of different colours, i.e. violet plates for (I) and blue needles for (II), both of which were analysed by X-ray crystallography. The 3,3'-TPDC bridging ligands coordinate the Cu(II) ions in asymmetric chelating modes in (I) and in monodenate binding modes in (II), forming one-dimensional chains in each case. Both coordination polymers contain two coordinated dimethylamine ligands in mutually trans positions, and there is an additional aqua ligand in (II). The solvent water molecules are involved in hydrogen bonds between the one-dimensional coordination polymer chains, forming a two-dimensional network in (I) and a three-dimensional network in (II).

A new three-dimensional bis(benzimidazole)-based cadmium(II) coordination polymer

NASA Astrophysics Data System (ADS)

Hao, Shao Yun; Hou, Suo Xia; Hao, Zeng Chuan; Cui, Guang Hua

2018-01-01

A new coordination polymer (CP), formulated as [Cd(L)(DCTP)]n (1) (L = 1,1‧-(1,4-butanediyl)bis(2-methylbenzimidazole), H2DCTP = 2,5-dichloroterephthalic acid), was synthesized under hydrothermal conditions and the performance as luminescent probe was also investigated. Single-crystal X-ray diffraction reveals CP 1 is a 3D 3-fold interpenetrated dia network with large well-defined pores. It is found that CP 1 revealed highly sensitive luminescence sensing for Fe3 + ions in acetonitrile solution with a high quenching efficiency of KSV = 2541.238 L·mol- 1 and a low detection limit of 3.2 μM (S/N = 3). Moreover, the photocatalytic efficiency of 1 for degradation of methylene blue could reach 82.8% after 135 min. Therefore, this coordination polymer could be viewed as multifunctional material for selectively sensing Fe3 + ions and effectively degrading dyes.

Water molecule-enhanced CO{sub 2} insertion in lanthanide coordination polymers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo Liushan; Huang Xiaoyuan; Wang Ning

2009-08-15

Two new lanthanide coordination polymers H{sub 2}N(CH{sub 3}){sub 2}.[Eu{sup III}{sub 2}(L{sub 1}){sub 3}(L{sub 2})] (1, L{sub 1}=isophthalic acid dianion, L{sub 2}=formic acid anion) and [La{sup III}(2,5-PDC)(L{sub 2})](2, 2,5-PDC=2,5-pyridinedicarboxylate dianion) were synthesized under solvothermal conditions. It is of interest that the formic ligand (L{sub 2}) is not contained in the stating materials, but arises from the water molecule-enhanced CO{sub 2} insertion during the solvothermal process. Both of the two compounds exhibit complicated three dimensional sandwich-like frameworks. - Graphical abstract: Two new lanthanide coordination polymers involving water molecule-enhanced CO{sub 2} insertion resulting in the formation of formic anion and dimethylammonium cation weremore » synthesized under solvothermal conditions.« less

Zinc coordination polymers containing substituted isophthalate ligands and fragments from in situ hydrolysis of 4-pyridylisonicotinamide

NASA Astrophysics Data System (ADS)

O'Donovan, Megan E.; LaDuca, Robert L.

2015-03-01

Hydrothermal treatment of zinc nitrate, a 5-substituted isophthalic acid, and 4-pyridylisonicotinamide (4-pina) resulted in crystalline coordination polymers that incorporated different fragments formed by in situ hydrolysis of the 4-pina precursor. These materials were characterized by single crystal X-ray diffraction. In the case of {[4-ampyrH]2[Zn(hip)2]·H2O}n (1, 4-ampyrH = 4-aminopyridinium, hip = 5-hydroxyisophthalate), anionic [Zn(hip)2]n2n- (4,4) grid layers co-crystallize with protonated 4-ampyr cations. Using 5-nitroisophthalic acid (H2nip), [Zn7(isonic)4(OH)6(nip)2]n (2, isonic = isonicotinate) was formed. This material manifests [Zn7(OH)6]n cationic inorganic chain motifs linked by isonic and nip ligands into a non-interpenetrated 3-D coordination polymer network with pcu topology. Luminescent behavior is attributed to intra-ligand molecular orbital transitions.

Extending the lanthanide-terephthalate system: Isolation of an unprecedented Tb(III)-based coordination polymer with high potential porosity and luminescence properties

NASA Astrophysics Data System (ADS)

Le Natur, François; Calvez, Guillaume; Freslon, Stéphane; Daiguebonne, Carole; Bernot, Kevin; Guillou, Olivier

2015-04-01

A novel coordination polymer with chemical formula {[Tb(bdc)1.5(H2O)]ṡ(DMF)(H2O)}∞ (1) has been synthesized by reaction between 1,4-benzene-dicarboxylic acid (H2bdc) and di-cationic hexanuclear entity [Tb6O(OH)8(NO3)6(H2O)12]2+ in an ethylene glycol (EG)/N,N-dimethylformamide (DMF) mixture. This compound has been obtained as single crystals by slow evaporation in air at room temperature. If the hexanuclear entity is destroyed during the reaction, the coordination polymer that is obtained is original and presents promising potential micro-porosity and luminescent properties. It crystallizes in the monoclinic system, space group C12/c1 (No. 15) with the cell parameters a = 23.7540(1) Å, b = 10.5390(4) Å, c = 19.7580(3) Å, β = 125.8100(1)° and Z = 8.

Recovery of metals from simulant spent lithium-ion battery as organophosphonate coordination polymers in aqueous media.

PubMed

Perez, Emilie; Andre, Marie-Laure; Navarro Amador, Ricardo; Hyvrard, François; Borrini, Julien; Carboni, Michaël; Meyer, Daniel

2016-11-05

An innovative approach is proposed for the recycling of metals from a simulant lithium-ion battery (LIBs) waste aqueous solution. Phosphonate organic linkers are introduced as precipitating agents to selectively react with the metals to form coordination polymers from an aqueous solution containing Ni, Mn and Co in a hydrothermal process. The supernatant is analyzed by ICP-AES to quantify the efficiency and the selectivity of the precipitation and the materials are characterized by Scanning Electron Microscopy (SEM), Powder X-Ray Diffraction (PXRD), Thermogravimetric Analyses (TGA) and nitrogen gas sorption (BET). Conditions have been achieved to selectively precipitate Manganese or Manganese/Cobalt from this solution with a high efficiency. This work describes a novel method to obtain potentially valuable coordination polymers from a waste metal solution that can be generalized on any waste solution. Copyright © 2016 Elsevier B.V. All rights reserved.

The Researching on Evaluation of Automatic Voltage Control Based on Improved Zoning Methodology

NASA Astrophysics Data System (ADS)

Xiao-jun, ZHU; Ang, FU; Guang-de, DONG; Rui-miao, WANG; De-fen, ZHU

2018-03-01

According to the present serious phenomenon of increasing size and structure of power system, hierarchically structured automatic voltage control(AVC) has been the researching spot. In the paper, the reduced control model is built and the adaptive reduced control model is researched to improve the voltage control effect. The theories of HCSD, HCVS, SKC and FCM are introduced and the effect on coordinated voltage regulation caused by different zoning methodologies is also researched. The generic framework for evaluating performance of coordinated voltage regulation is built. Finally, the IEEE-96 stsyem is used to divide the network. The 2383-bus Polish system is built to verify that the selection of a zoning methodology affects not only the coordinated voltage regulation operation, but also its robustness to erroneous data and proposes a comprehensive generic framework for evaluating its performance. The New England 39-bus network is used to verify the adaptive reduced control models’ performance.

Coordination Polymer Gels with Modular Nanomorphologies, Tunable Emissions, and Stimuli-Responsive Behavior Based on an Amphiphilic Tripodal Gelator.

PubMed

Sutar, Papri; Maji, Tapas Kumar

2017-08-21

The recent upsurge in research on coordination polymer gels (CPGs) stems from their synthetic modularity, nanoscale processability, and versatile functionalities. Here we report self-assembly of an amphiphilic, tripodal low-molecular weight gelator (L) that consists of 4,4',4-[1,3,5-phenyl-tri(methoxy)]-tris-benzene core and 2,2':6',2″-terpyridyl termini, with different metal ions toward the formation of CPGs that show controllable nanomorphologies, tunable emission, and stimuli-responsive behaviors. L can also act as a selective chemosensor for Zn II with very low limit of detection (0.18 ppm) in aqueous medium. Coordination-driven self-assembly of L with Zn II in H 2 O/MeOH solvent mixture results in a coordination polymer hydrogel (ZnL) that exhibits sheet like morphology and charge-transfer emission. On the other hand, coordination of L with Tb III and Eu III in CHCl 3 /tetrahydrofuran solvent mixture results in green- and red-emissive CPGs, respectively, with nanotubular morphology. Moreover, precise stoichiometric control of L/Eu III /Tb III ratio leads to the formation of bimetallic CPGs that show emissions over a broad spectral range, including white-light-emission. We also explore the multistimuli responsive properties of the white-light-emitting CPG by exploiting the dynamics of Ln III -tpy coordination.

Self-Assembled ROS-Sensitive Polymer-Peptide Therapeutics Incorporating Built-in Reporters for Evaluation of Treatment Efficacy.

PubMed

Qiao, Zeng-Ying; Zhao, Wen-Jing; Cong, Yong; Zhang, Di; Hu, Zhiyuan; Duan, Zhong-Yu; Wang, Hao

2016-05-09

One of the major challenges in current cancer therapy is to maximize therapeutic effect and evaluate tumor progression under the scheduled treatment protocol. To address these challenges, we synthesized the cytotoxic peptide (KLAKLAK)2 (named KLAK) conjugated amphiphilic poly(β-thioester)s copolymers (H-P-K) composed of reactive oxygen species (ROS) sensitive backbones and hydrophilic polyethylene glycol (PEG) side chains. H-P-K could self-assemble into micelle-like nanoparticles by hydrophobic interaction with copolymer backbones as cores and PEG and KLAK as shells. The assembled polymer-peptide nanoparticles remarkably improved cellular internalization and accumulation of therapeutic KLAK in cells. Compared to free KLAK peptide, the antitumor activity of H-P-K was significantly enhanced up to ∼400 times, suggesting the effectiveness of the nanoscaled polymer-peptide conjugation as biopharmaceuticals. The higher antitumor activity of nanoparticles was attributed to the efficient disruption of mitochondrial membranes and subsequent excessive ROS production in cells. To realize the ROS monitoring and treatment evaluation, we encapsulated squaraine (SQ) dyes as built-in reporters in ROS-sensitive H-P-K micelles. The overgenerated ROS around mitochondria stimulated the swelling of nanoparticles and subsequent release of SQ, which formed H-aggregates and significantly increased the photoacoustic (PA) signal. We believed that this self-assembled polymer-peptide nanotherapeutics incorporating built-in reporters has great potential for high antitumor performance and in situ treatment evaluation.

Alkaline earth-based coordination polymers derived from a cyclotriphosphazene-functionalized hexacarboxylate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ling, Yajing; Bai, Dongjie; Feng, Yunlong

Combination of hexakis(4-carboxylatephenoxy)cyclotriphosphazene with alkaline earth ions of increasing ionic radii (Mg{sup 2+}, Ca{sup 2+} and Ba{sup 2+}) under different solvothermal conditions yielded three new coordination polymers, and their crystal structures were determined by single-crystal X-ray diffraction analysis. The magnesium compound displays a three dimensional (3D) network structure constructed from the deprotonated ligand and the secondary building block Mg(COO){sub 4}, which can be rationalized as a (4,6)-connected topological net with the Schläfli symbol of (4{sup 4}·6{sup 2}){sub 3}(4{sup 9}·6{sup 6}){sub 2}. The calcium compound consists of 1D infinite “Ca-O” inorganic chains connected by the deprotonated ligands to from a 3Dmore » framework. The barium compound exhibits a 3D framework in which 1D “Ba-O” inorganic chains are connected together by the deprotonated organic linkers. Due to the semi-rigid nature, the ligand adopts distinctly different conformations in the three compounds. The metal ions’ influence exerted on the final structure of the resulting coordination polymers is also discussed. When the radii of alkaline earth ions increases descending down the group from Mg(II) to Ba(II), the coordination number becomes larger and more versatile: from 6 in the magnesium compound, to 6,7 and 10 in the calcium compound, and to 8 and 9 in the barium compound, thus substantially influencing the resulting final framework structures. Also, the photophysical properties were investigated systematically, revealing that the three compounds are photoluminscent in the solid state at room temperature. This work demonstrates that although the multiplicity of conformation in the hexacarboxylate ligand based on the inorganic scaffold cyclotriphosphazene makes it difficult to predict how this ligand will form extended network, but provides unique opportunities for the formation of diverse inorganic-organic hybrids exhibiting rich structural topologies. - Graphical abstract: Three alkaline earth-based coordination polymers were constructed from a semirigid cyclotriphosphazene-functionalized hexacarboxylate exhibiting different inorganic nodes as well as distinct ligand conformations relying on the metal ions, which presents the first example of such a ligand incorporated into alkaline earth–based coordination polymers. - Highlights: • Three alkaline earth-based coordination polymers were synthesized. • The three compounds exhibit different inorganic nodes and ligand conformations. • The three compounds are photoluminscent in the solid state.« less

Syntheses, structures and characterization of isomorphous CoII and NiII coordination polymers based on 2-[(1H-imidazol-1-yl)methyl]-6-methyl-1H-benzimidazole and benzene-1,4-dicarboxylate.

PubMed

Huang, Qiu Ying; Zhao, Yang; Meng, Xiang Ru

2017-08-01

Careful choice of the organic ligands is one of the most important parameters in the rational design and synthesis of coordination polymers. Aromatic polycarboxylates have been widely used in the preparation of metal-organic polymers since they can utilize various coordination modes to form diverse structures and can act as hydrogen-bond acceptors and donors in the assembly of supramolecular structures. Nitrogen-heterocyclic organic compounds have also been used extensively as ligands for the construction of polymers with interesting structures. In the polymers catena-poly[[[diaquabis{2-[(1H-imidazol-1-yl)methyl]-6-methyl-1H-benzimidazole-κN 3 }cobalt(II)]-μ 2 -benzene-1,4-dicarboxylato-κ 2 O 1 :O 4 ] dihydrate], {[Co(C 8 H 4 O 4 )(C 12 H 11 N 4 ) 2 (H 2 O) 2 ]·2H 2 O} n , (I), and catena-poly[[[diaquabis{2-[(1H-imidazol-1-yl)methyl]-6-methyl-1H-benzimidazole-κN 3 }nickel(II)]-μ 2 -benzene-1,4-dicarboxylato-κ 2 O 1 :O 4 ] dihydrate], {[Ni(C 8 H 4 O 4 )(C 12 H 11 N 4 ) 2 (H 2 O) 2 ]·2H 2 O} n , (II), the Co II or Ni II ion lies on an inversion centre and exhibits a slightly distorted octahedral coordination geometry, coordinated by two N atoms from two imidazole rings and four O atoms from two monodentate carboxylate groups and two water molecules. The dicarboxylate ligands bridge metal ions forming a polymeric chain. The 2-[(1H-imidazol-1-yl)methyl]-6-methyl-1H-benzimidazole ligands coordinate to the Co II or Ni II centres in monodentate modes through an imidazole N atom and are pendant on opposite sides of the main chain. The two structures are isomorphous. In the crystal, the one-dimensional chains are further connected through O-H...O, O-H...N and N-H...O hydrogen bonds, leading to a three-dimensional supramolecular architecture. In addition, the IR spectroscopic properties, PXRD patterns, thermogravimetric behaviours and fluorescence properties of both polymers have been investigated.

Functional Two-Dimensional Coordination Polymeric Layer as a Charge Barrier in Li-S Batteries.

PubMed

Huang, Jing-Kai; Li, Mengliu; Wan, Yi; Dey, Sukumar; Ostwal, Mayur; Zhang, Daliang; Yang, Chih-Wen; Su, Chun-Jen; Jeng, U-Ser; Ming, Jun; Amassian, Aram; Lai, Zhiping; Han, Yu; Li, Sean; Li, Lain-Jong

2018-01-23

Ultrathin two-dimensional (2D) polymeric layers are capable of separating gases and molecules based on the reported size exclusion mechanism. What is equally important but missing today is an exploration of the 2D layers with charge functionality, which enables applications using the charge exclusion principle. This work demonstrates a simple and scalable method of synthesizing a free-standing 2D coordination polymer Zn 2 (benzimidazolate) 2 (OH) 2 at the air-water interface. The hydroxyl (-OH) groups are stoichiometrically coordinated and implement electrostatic charges in the 2D structures, providing powerful functionality as a charge barrier. Electrochemical performance of the Li-S battery shows that the Zn 2 (benzimidazolate) 2 (OH) 2 coordination polymer layers efficiently mitigate the polysulfide shuttling effects and largely enhance the battery capacity and cycle performance. The synthesis of the proposed coordination polymeric layers is simple, scalable, cost saving, and promising for practical use in batteries.

Integrated Evaluation of Coupling Coordination for Land Use Change and Ecological Security: A Case Study in Wuhan City of Hubei Province, China

PubMed Central

Wang, Zhanqi; Zhang, Hongwei

2017-01-01

As land resources and ecosystems provide necessary materials and conditions for human development, land use change and ecological security play increasingly important roles in sustainable development. This study aims to reveal the mutual-influence and interaction between land use change and ecological security in Wuhan, based on the coupling coordination degree model. As such, it provides strategies for the achievement of the synchronous and coordinated development of urbanization and ecological security. The results showed that, during the period from 2006 to 2012, the size of built-up area in Wuhan increased to 26.16%, and that all the other types of land use reduced due to the urbanization process, which appeared to be the main driving force of land use change. The ecological security in Wuhan has been improving as a whole although it was somewhat held back from 2006 to 2008 due to the rapid growth of built-up area. The coupling coordination analysis revealed that the relationship between built-up area and ecological security was more coordinated after 2008. The results can provide feasible recommendations for land use management and environmental protection from the viewpoint of coordinated development. To achieve sustainable development from economic and ecological perspective, policy makers should control the rate of urban expansion and exert more effort on intensive land use, clean energy development and emission reduction. PMID:29165365

Integrated Evaluation of Coupling Coordination for Land Use Change and Ecological Security: A Case Study in Wuhan City of Hubei Province, China.

PubMed

Chai, Ji; Wang, Zhanqi; Zhang, Hongwei

2017-11-22

As land resources and ecosystems provide necessary materials and conditions for human development, land use change and ecological security play increasingly important roles in sustainable development. This study aims to reveal the mutual-influence and interaction between land use change and ecological security in Wuhan, based on the coupling coordination degree model. As such, it provides strategies for the achievement of the synchronous and coordinated development of urbanization and ecological security. The results showed that, during the period from 2006 to 2012, the size of built-up area in Wuhan increased to 26.16%, and that all the other types of land use reduced due to the urbanization process, which appeared to be the main driving force of land use change. The ecological security in Wuhan has been improving as a whole although it was somewhat held back from 2006 to 2008 due to the rapid growth of built-up area. The coupling coordination analysis revealed that the relationship between built-up area and ecological security was more coordinated after 2008. The results can provide feasible recommendations for land use management and environmental protection from the viewpoint of coordinated development. To achieve sustainable development from economic and ecological perspective, policy makers should control the rate of urban expansion and exert more effort on intensive land use, clean energy development and emission reduction.

Syntheses, structures and luminescent properties of a series of 3D lanthanide coordination polymers with tripodal semirigid ligand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qin Junsheng; Department of Applied Chemistry, Jilin Institute of Chemical Technology, Jilin 132022; Du Dongying

2011-02-15

Reactions of the tripodal bridging ligand 5-(4-carboxy-phenoxy)-isophthalic acid (abbreviated as H{sub 3}cpia) with lanthanide salts lead to the formation of a family of different coordination polymers, that is, [Ln(cpia)(H{sub 2}O){sub 2}]{sub n}.nH{sub 2}O (Ln=Ce (1), Pr (2), Nd (3), Sm (4), Eu (5), Gd (6), Dy (7), Er (8), Tm (9) and Y (10)) in the presence of formic acid or diethylamine, which are characterized by elemental analysis, IR spectrum, thermogravimetric analysis (TGA), XRPD spectrum and single-crystal X-ray diffraction. Compounds 1-10 are isostructural and exhibit three-dimensional microporous frameworks. Furthermore, the photoluminescent properties of 4, 5 and 7 have been studiedmore » in detail. -- Graphical abstract: Reactions of the tripodal bridging ligand (H{sub 3}cpia) with lanthanide ions lead to the formation of a series of coordination polymers in the presence of formic acid or diethylamine. Display Omitted Research Highlights: {yields} Ten new lanthanides-based coordination polymers (1-10) have been synthesized. {yields} 1-10 exhibit 3D (4,8)-connected fluorite topology networks with 1D channel parallel to the b-axis. {yields} Compounds 4, 5 and 7 exhibit characteristic luminescence of Sm{sup 3+}, Eu{sup 3+} and Dy{sup 3+} ions, respectively.« less

Mercury coordination polymers with flexible ethane-1,2-diyl-bis-(pyridyl-3-carboxylate): Synthesis, structures, thermal and luminescent properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vallejos, Javier; Brito, Iván, E-mail: ivanbritob@yahoo.com; Cárdenas, Alejandro

2015-03-15

The reaction of the flexible ligand, ethane-1,2-diyl-bis-(pyridyl-3-carboxylate), (L) with HgI{sub 2} and HgBr{sub 2} salts under the same experimental conditions leads to the formation of two coordination polymers with different motifs: ([Hg(L)(Br{sub 2})]){sub n}(1) and ([Hg(L)(I{sub 2})]){sub n}(2). In both compounds, the ligand, (L) acts in a μ2-N:N′-bidentate fashion to link HgBr{sub 2} and HgI{sub 2} units to form a linear and helical chain motif, along [1 0 0] for (1) and [0 0 1] for (2). The ethylene moiety of (L) has gauche and trans conformation in compounds (1) and (2), respectively. The flexible conformation of L produces differencesmore » in the optical and crystal properties of the two compounds. - Graphical abstract: This work demonstrates how the HgX{sub 2} units are coordinates by bi-dentate ligand forming polymeric coordination complexes by self-assembly of both chemical units.- Highlights: • News 1-D d{sup 10} transition metal coordination polymers. • The photoluminescent properties have been measured. • The thermal properties have been measured.« less

ECM-Based Biohybrid Materials for Engineering Compliant, Matrix-Dense Tissues

PubMed Central

Bracaglia, Laura G.; Fisher, John P.

2015-01-01

An ideal tissue engineering scaffold should not only promote, but take an active role in, constructive remodeling and formation of site appropriate tissue. ECM-derived proteins provide unmatched cellular recognition, and therefore influence cellular response towards predicted remodeling behaviors. Materials built with only these proteins, however, can degrade rapidly or begin too weak to substitute for compliant, matrix-dense tissues. The focus of this review is on biohybrid materials that incorporate polymer components with ECM-derived proteins, to produce a substrate with desired mechanical and degradation properties, as well as actively guide tissue remodeling. Materials are described through four fabrication methods: (1) polymer and ECM-protein fibers woven together, (2) polymer and ECM proteins combined in a bilayer, (3) cell-built ECM on polymer scaffold, and (4) ECM proteins and polymers combined in a single hydrogel. Scaffolds from each fabrication method can achieve characteristics suitable for different types of tissue. In vivo testing has shown progressive remodeling in injury models, and suggests ECM-based biohybrid materials promote a prohealing immune response over single component alternatives. The prohealing immune response is associated with lasting success and long term host maintenance of the implant. PMID:26227679

Synthesis and characterization of multifunctional coordination polymer of the type [CuxNi1-x(dedb)·2H2O]n

NASA Astrophysics Data System (ADS)

Singh, Deepshikha; Kushwaha, Anita; Banerjee, A.; Prasad, R. L.

2015-07-01

New series of multifunctional homometallic and heterobimetallic coordination polymers of the type [CuxNi1-x(dedb)·2H2O]n {where dedb = dianion of 2,5-dichloro-3,6-bis(ethylamino)-1,4-benzoquinone (1); x = 1, (2); 0 (3); 0.5 (4); 0.25 (5); 0.125 (6); 0.0625 (7) and n = degree of polymerization} have been synthesized and characterized by Powder X-ray diffraction, IR, UV-visible and ESR spectroscopic techniques. Variable temperature susceptibility measurement indicates presence of strong ferromagnetic interaction. The effects of copper doping on thermal, magnetic and conducting properties of these polymers have been investigated in this communication. A rare co-existence of ferromagnetism as well as electrical conductivity has been observed in these polymers.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Wen-Hua; Yan, Hao-Jie; Chen, Hui

Dipyridyl sulphide ligands 4-(pyridin-4-ylmethylthio)pyridine (abbreviated as L1) and 3-(pyridin-4-ylmethylthio)pyridine (abbreviated as L2) have been designed and used as μ-{sub N},{sub N}-bridging linkages to construct coordination polymers with free –S–CH{sub 2}– groups as secondary donor sites. By use solvent control method, coordination polymers ([Ag{sub 3}SO{sub 4}(L1){sub 3}](Cl)·4.5H{sub 2}O){sub ∞}(1), ([Ag{sub 2}SO{sub 4}(L1){sub 2}]·6H{sub 2}O·2CH{sub 3}OH){sub ∞}(2), ([Ag{sub 2}SO{sub 4}(L2){sub 2}]·H{sub 2}O){sub ∞}(3) and ([Ag{sub 4}(SO{sub 4}){sub 2}(L2){sub 4}]·5H{sub 2}O){sub ∞}(4) with different architectures were obtained. Complexes 1, 3 and 4 feature 1D channel with different sizes and structures. Complex 1 exhibits guest exchange by THF and 1,4-dioxane, and Hg{sup 2+} sorptionmore » ability from solution due to its relative larger channel and available bonding sites of –S– exposed to the channel region. All complexes have been characterized through single-crystal and powder X-ray diffraction (PXRD), FT-IR spectra, X-ray photoelectron spectroscopy (XPS), elemental and thermogravimetric analyses. The guest exchange and Hg{sup 2+} sorption were monitored and identified, and the structure-property relationship of coordination polymers 1–4 are discussed. - Graphical abstract: Coordination polymers of silver(I) sulfate with secondary donor sites are shown guest exchange property and Hg{sup 2+} absorb ability from solution. This work provides a new method to construct functional materials with potential application. - Highlights: • New example of constructing functional coordination polymer with secondary donor methylthio group. • Guest exchange and interesting Hg(II) absorb ability from solution are investigated. • New method to construct functional materials with potential application.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yao, Shuang; Yi, Fei-Yan; Li, Guanghua

Two coordination polymers [Co{sub 2}(TA)(4,4′-bipy){sub 2}(H{sub 2}O){sub 2}]·H{sub 2}O (1) and [Ni{sub 2}(TA)(4,4′-bipy){sub 2}(H{sub 2}O){sub 4}]·3H{sub 2}O (2) were prepared by hydrothermal reactions of MCl{sub 2}·6H{sub 2}O (M = Co, Ni) with a V-shaped ligand TDPA (3,3′,4,4′-thiodiphthalic anhydride) and a I-shaped N-donor co-ligand (4,4′-bipy). They were characterized by elemental analyses, thermogravinetric analyses, and magnetic behavior. As is expected, TDPA hydrolyzes into the corresponding tetra-carboxylate acid H{sub 4}TA (3,3′,4,4′-thiodiphthalic acid) during the reactions. Co{sub 2} dimer and Ni mononuclear center are connected into two-dimensional (2D) layers by H{sub 4}TA and 4,4′-bipy bridge in 1 and 2, respectively. The most amazing featuremore » is that 1 and 2 exhibit interesting spin-canting metamagnetism and weak ferromagnetic behavior, respectively, with the critical Néel temperature of T{sub N} =4 K for 1 and T{sub N} =13 K for 2, based on variable temperature magnetic susceptibility measurements. In low mono- or dinuclear metal system, such magnetic behaviors have rare been observed. Furthermore, complex 1 will be a potential metamagnet material. - Graphical abstract: Two Co(II) and Ni(II) coordination polymers were synthesized by hydrothermal reactions from a V-shape ligand (3,3′,4,4′-thiodiphthalic anhydride) and a I-shape ligand (4,4′-bipy), which were characterized by single crystal X-ray diffraction, elemental analyses, thermogravinetric analyses, and magnetic behavior, and exhibit interesting spin-canting metamagnetism and weak ferromagnetic behavior, respectively. - Highlights: • Two Co(II) and Ni(II) coordination polymers were successfully synthesized. • Co(II) coordination polymer shows an interesting spin-canting metamagnetism. • Ni(II) coordination polymer exhibits a weak ferromagnetic behavior.« less

A family of silver(I) complexes built with 2-sulfoterephthalic acid monosodium salt and different aminopyridine ligands: Syntheses, structures and properties

NASA Astrophysics Data System (ADS)

Zhang, Jie; Tan, Gai-Xiu; Liu, Bao-Lin; Dai, Yu-Bei; Xu, Na; Wen, Wei-Fen; Cao, Chong; Xiao, Hong-Ping

2017-05-01

Five Ag(I) coordination complexes, namely, [Ag6(2-stp)2(3-methyl-2-apy)3·H2O]n (1), [Ag3(2-stp)(4-methyl-2-apy)3]n (2), [Na2Ag18(2-stp)4(2-Hstp)4(5-methyl-2-apy)16 (H2O)4·11H2O]n (3), Ag3(2-stp)(6-methy-2-apy)4·H2O (4), and [Ag6(2-stp)2(6-methyl-2-apy)8(H2O)2·H2O]n (5) (2-NaH2stp = 2-sulfoterephthalic acid monosodium salt, 3-methyl-2-apy = 3-methyl-2-aminopyridine, 4-methyl-2-apy = 4-methyl-2-aminopyridine, 5-methyl-2-apy = 5-methyl-2-aminopyridine, 6-methyl-2-apy = 6-methyl-2-aminopyridine), have been synthesized and structurally characterized. Complexes 1 and 2 show two-dimensional network. In complex 3, the adjacent Ag10 units are bridged by 5-methyl-2-apy ligands to form a 2D infinite undulated sheet. Adjacent 2D sheets are linked by coordinative bonds between carboxylic oxygen atoms and Na(I) ions to form a 3D coordination polymer. Complex 4 is a 0-D discrete trinuclear molecule, and the self-complementary the Osbnd H⋯O and Nsbnd H⋯O hydrogen bonds incorporating hydrogen bond motifs extend these molecules into a 2D supramolecular framework. Compound 5 exhibits 1D-chain structure. However, complex 5 shows 3D supramolecular structure results from the linkage of neighboring layers through a rich hydrogen-bonding between uncoordinated sulfonates, amino groups and coordinated carboxylates. The thermogravimetric analyses and photoluminescence of the complexes were also investigated.

Localization of source with unknown amplitude using IPMC sensor arrays

NASA Astrophysics Data System (ADS)

Abdulsadda, Ahmad T.; Zhang, Feitian; Tan, Xiaobo

2011-04-01

The lateral line system, consisting of arrays of neuromasts functioning as flow sensors, is an important sensory organ for fish that enables them to detect predators, locate preys, perform rheotaxis, and coordinate schooling. Creating artificial lateral line systems is of significant interest since it will provide a new sensing mechanism for control and coordination of underwater robots and vehicles. In this paper we propose recursive algorithms for localizing a vibrating sphere, also known as a dipole source, based on measurements from an array of flow sensors. A dipole source is frequently used in the study of biological lateral lines, as a surrogate for underwater motion sources such as a flapping fish fin. We first formulate a nonlinear estimation problem based on an analytical model for the dipole-generated flow field. Two algorithms are presented to estimate both the source location and the vibration amplitude, one based on the least squares method and the other based on the Newton-Raphson method. Simulation results show that both methods deliver comparable performance in source localization. A prototype of artificial lateral line system comprising four ionic polymer-metal composite (IPMC) sensors is built, and experimental results are further presented to demonstrate the effectiveness of IPMC lateral line systems and the proposed estimation algorithms.

Three coordination polymers constructed from 5-(4-(tetrazol-5-yl)phenyl)isophthalic acid: Synthesis, crystal structure and properties

NASA Astrophysics Data System (ADS)

Zhai, Dandan; Sun, Wujuan; Fan, Fei; Liao, Xuzhao; Chen, Sanping; Yang, Xuwu

2017-04-01

Three new coordination polymers, namely, {[Co2(TPA)(μ3-O)3]·0.5DMA}n (1), {[Co(H2TPA)(bibp)(H2O)3]·H2O}n (2) and {[Cd3(TPA)2(phen)4]·4H2O}n (3), (H3TPA = 5-(4-(tetrazol-5-yl)phenyl)isophthalic acid, bibp = 4,4'-bis(imidazolyl)biphenyl, phen = 1,10-phenanthroline and DMA = N,N-dimethylacetamide), have been synthesized under solvothermal conditions and structurally characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction analysis. Polymer 1 exhibits a three-dimensional (3D) structure constructed from 5-connected secondary building units (SBUs) [Co3(μ3-O)] and 3-connected H3TPA ligands. Polymer 2 has a 1D zigzag polymer chain connected by H3TPA and bibp ligands. Polymer 3 features an unusual 3D framework with a (3,4,2)-connected {4; 6;8}{4; 62;83} topology. Moreover, the thermal stabilities of 1-3 and photoluminescence properties of 3 have been investigated. Magnetic susceptibility measurements indicate that polymers 1-2 display antiferromagnetic exchange properties.

Four unexpected lanthanide coordination polymers involving in situ reaction of solvent N, N-Dimethylformamide

NASA Astrophysics Data System (ADS)

Jin, Jun-Cheng; Tong, Wen-Quan; Fu, Ai-Yun; Xie, Cheng-Gen; Chang, Wen-Gui; Wu, Ju; Xu, Guang-Nian; Zhang, Ya-Nan; Li, Jun; Li, Yong; Yang, Peng-Qi

2015-05-01

Four unexpected 2D lanthanide coordination polymers have been synthesized through in situ reactions of DMF solvent under solvothermal conditions. The isostructural complexes 1-3 contain four types of 21 helical chains. While the Nd(III) ions are bridged through μ2-HIDC2- and oxalate to form a 2D sheet along the bc plane without helical character in 4. Therefore, complex 1 exhibits bright red solid-state phosphorescence upon exposure to UV radiation at room temperature.

Heterobimetallic coordination polymers involving 3d metal complexes and heavier transition metals cyanometallates

NASA Astrophysics Data System (ADS)

Peresypkina, Eugenia V.; Samsonenko, Denis G.; Vostrikova, Kira E.

2015-04-01

The results of the first steps in the design of coordination polymers based on penta- and heptacyanometallates of heavier d transitions metals are presented. The 2D structure of the coordination polymers: [{Mn(acacen)}2Ru(NO)(CN)5]n and two complexes composed of different cyanorhenates, [Ni(cyclam)]2[ReO(OH)(CN)4](ClO4)2(H2O)1.25 and [Cu(cyclam)]2[Re(CN)7](H2O)12, was confirmed by single crystal XRD study, the rhenium oxidation state having been proved by the magnetic measurements. An amorphism of [M(cyclam)]3[Re(CN)7]2 (M=Ni, Cu) polymers does not allow to define strictly their dimensionality and to model anisotropic magnetic behavior of the compounds. However, with high probability a honey-comb like layer structure could be expected for [M(cyclam)]3[Re(CN)7]2 complexes, studied in this work, because such an arrangement is the most common among the bimetallic assemblies of hexa- and octacyanometallates with a ratio [M(cyclam)]/[M(CN)n]=3/2. For the first time was prepared and fully characterized a precursor (n-Bu4N)2[Ru(NO)(CN)5], soluble in organic media.

Synthesis and characterization of two new zinc(II) coordination polymers with bidentate flexible ligands: Formation of a 2D structure with (44.62)-sql topology

NASA Astrophysics Data System (ADS)

Lalegani, Arash; Khaledi Sardashti, Mohammad; Gajda, Roman; Woźniak, Krzysztof

2017-12-01

Zinc(II) coordination polymers [Zn(bip)2(NCS)2]n (1) and [Zn(μ-bbd)(N3)2]n (2) were synthesized by using the neutral flexible bidentate N-donor ligands 1,4-bis(3,5-dimethylpyrazolyl)butane (bbd) and 1,3-bis(imidazolyl)propane (bip), mono-anionic NCS- or N3-ligand and zinc(II) chloride salts. The results of the X-ray analyses demonstrate that in the structure of 1, the zinc(II) ion is located on an inversion center and exhibits an ZnN6 octahedral arrangement while, in the structure of 2, the zinc(II) ion adopts an ZnN4 tetrahedral geometry. In the polymer 1, the NCS groups are terminally N-bonded to the metal center and the each bip with anti-gauche conformation acts as bridging connecting four zinc(II) ions to form a two-dimensional network with a sql [point symbol (44.62)] topology while, in the polymer 1, the N3 groups are terminally bonded to the metal center and each bbd with anti-anti-anti conformation acts as bridging ligand connecting two zinc(II) ions to form a one-dimensional zig-zag chain. Coordination compounds 1 and 2 have been characterized by infrared spectroscopy, elemental analyses and single-crystal X-ray diffraction. Thermal analyses of polymers were also presented.

[2D correlation spectral study of a coordination polymer [Eu(PCPOA)3 (H2O)]n].

PubMed

Sun, Rui-qing; Zhang, Han-hui; Cao, Yan-ning; Chen, Yi-ping; Yang, Qi-yu; Wang, Zhi-yang

2007-05-01

A novel two dimensional coordination polymer [Eu(PCPOA)3 (H2O)], was synthesized under hydrothermal condition. Based on the determination of the structure, the 2D correlation FTIR spectra with the perturbation of magnetism and the 2D correlation fluorescence spectra with the perturbation of temperature were investigated. The energy bonds were calculated using CASTEP Program of Material studio. The Europium ions are nine-coordinated and the ligands adopted two different modes to connect the Eu3+ ions to 2D layer structure. The study of the 2D-FTIR reveals that the carboxylates coordinate with the center ions not only as monodentate, but also as bidentate chelate. The 2D fluorescence spectra indicates that the transition of (5)D0-->(7)F2 is influenced intensively by the perturbation of temperature.

A new 1D manganese(II) coordination polymer with end-to-end azide bridge and isonicotinoylhydrazone Schiff base ligand: Crystal structure, Hirshfeld surface, NBO and thermal analyses

NASA Astrophysics Data System (ADS)

Khani, S.; Montazerozohori, M.; Masoudiasl, A.; White, J. M.

2018-02-01

A new manganese (II) coordination polymer, [MnL2 (μ-1,3-N3)2]n, with co-ligands including azide anion and Schiff base based on isonicotinoylhydrazone has been synthesized and characterized. The crystal structure determination shows that the azide ligand acts as end-to-end (EE) bridging ligand and generates a one-dimensional coordination polymer. In this compound, each manganes (II) metal center is hexa-coordinated by four azide nitrogens and two pyridinic nitrogens for the formation of octahedral geometry. The analysis of crystal packing indicates that the 1D chain of [MnL2 (μ-1,3-N3)2]n, is stabilized as a 3D supramolecular network by intra- and inter-chain intermolecular interactions of X-H···Y (X = N and C, Y = O and N). Hirshfeld surface analysis and 2D fingerprint plots have been used for a more detailed investigation of intermolecular interactions. Also, natural bond orbital (NBO) analysis was performed to get information about atomic charge distributions, hybridizations and the strength of interactions. Finally, thermal analysis of compound showed its complete decomposition during three thermal steps.

Molecular Motion in Polymers: Mechanical Behavior of Polymers Near the Glass-Rubber Transition Temperature.

ERIC Educational Resources Information Center

Sperling, L. H.

1982-01-01

The temperature at which the onset of coordinated segmental motion begins is called the glass-rubber transition temperature (Tg). Natural rubber at room temperature is a good example of a material above its Tg. Describes an experiment examining the response of a typical polymer to temperature variations above and below Tg. (Author/JN)

Formation of Gd coordination polymer with 1D chains mediated by Bronsted acidic ionic liquids

NASA Astrophysics Data System (ADS)

Luo, Qianqian; Han, Ying; Lin, Hechun; Zhang, Yuanyuan; Duan, Chungang; Peng, Hui

2017-03-01

One dimensional coordination polymer Gd[(SO4)(NO3)(C2H6SO)2] (1) is prepared through the mediation of Bronsted acid ionic liquid, which crystallized in the monoclinic space of C2/c. In this polymer, adjacent Gd atoms are linked by two SO42- ions to generate a 1-D chain, and all oxygen atoms in SO42- groups are connected to three nearest Gd atoms in μ3:η1:η1:η2 fashion. Gd, S and N from SO42- and NO3- are precisely coplanar. The planar is coordinated by a pair of DMSO molecules, which is parallel and linked by hydrogen bonding to form a three-dimensional supramolecular network. Magnetic susceptibility measurement of 1 reveals weak antiferromagnetic interactions between the Gd (III) ions. It exhibits relatively large magneto-caloric effect with -ΔSm=28.8 J Kg-1 K-1 for ΔH=7 T.

CdO-NPs; synthesis from 1D new nano Cd coordination polymer, characterization and application as anti-cancer drug for reducing the viability of cancer cells

NASA Astrophysics Data System (ADS)

Afzalian Mend, Behnaz; Delavar, Mahmoud; Darroudi, Majid

2017-04-01

The hexagonal CdO nano-particles (CdO-NPs) was prepared using new nano Cd coordination polymer, [Cd(NO3)(bipy)(pzca)]n (1) as a precursor, through direct calcination process at 500 °C. The precursor (1) was synthesized by sonochemical method. The new nano compound (1) was characterized by IR spectroscopy, elemental analyses, X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and thermal gravimetric analyses. The structure of nano coordination polymer was determined by comparing the XRD pattern of nano and single-crystal of compound (1). The nano CdO was characterized by scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). In addition, the activity and efficiency of nano CdO as an anti-cancer drug was studied on cancer cells with different concentration. The results shows that the viability of cancer cells reduced above 2 μg/mL of CdO-NPs concentration.

Studies on the relation between the size and dispersion of metallic silver nanoparticles and morphologies of initial silver(I) coordination polymer precursor

NASA Astrophysics Data System (ADS)

Moradi, Zhaleh; Akhbari, Kamran; Phuruangrat, Anukorn; Costantino, Ferdinando

2017-04-01

Micro and nano-structures of [Ag2(μ2-dcpa)2]n (1), [Hdcpa = 2,4-dichlorophenoxyacetic acid] which is a one-dimensional coordination polymer with corrugated tape chains, were synthesized as the bulk sample (1B), by sonochemical process (1S) and from mechanochemical reaction (1M). These three samples have been used as new precursors for fabricating silver nanoparticles via direct calcination at 300 °C and also thermal decomposition in oleic acid (OA) as a surfactant at 180 °C. In the presence of OA less agglomerated nanostructures were formed. It seems that the size, dispersion, morphology and agglomeration of initial precursor have direct influence on size, dispersion, morphology and agglomeration of metallic silver. This coordination polymer with various micro and nano morphologies were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). Thermal stability of these samples were studied and compared with each other, too.

Honeycomb-shaped coordination polymers based on the self-assembly of long flexible ligands and alkaline-earth ions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lian, Chen; Liu, Liu; Guo, Xu

2016-01-15

Two novel coordination polymers, namely, [Ca(NCP){sub 2}]{sub ∞} (I) and [Sr(NCP){sub 2}]{sub ∞} (II) were synthesized under hydrothermal conditions based on 2-(4-carboxyphenyl)imidazo(4,5-f)-(1,10)phenanthroline (HNCP) and characterized by elemental analysis, infrared spectrometry, X-ray powder diffraction and single crystal X-ray diffraction. Findings indicate that I and II are isomorphous and isostructural, containing the unit of M(NCP{sup −}){sub 4} (M=Ca(II) and Sr(II)), based on which to assemble into three-dimensional (3D) porous 4-fold interpenetration honeycomb-shaped neutral coordination polymers (CPs). Between the adjacent lamellar structures in I and II, there exist π–π interactions between the pyridine rings belonging to phenanthroline of NCP{sup −} which stabilize themore » frameworks. Both I and II display stronger fluorescence emissions as well as high thermal stability. - Graphical abstract: One-dimensional nanotubular channels with the cross dimension of 37.1959(20)×23.6141(11)Å{sup 2} in the three-dimensional honeycomb-shaped coordination network of II are observed. The topological analysis of II indicates that there exists a typical diamond framework possessing large adamantanoid cages, which containing four cyclohexane-shaped patterns in chair conformations. - Highlights: • Two isomorphous and isostructural coordination polymers based on flexible ligand and two alkaline-earth metal salts have been synthesized and characterized. • Structural analysis indicates that I and II are assembled into 3D porous honeycomb-shaped metal-organic frameworks. • Both I and II display stronger fluorescence emissions and higher thermal stability.« less

A two-dimensional layered Cd(II) coordination polymer with a three-dimensional supramolecular architecture incorporating mixed multidentate N- and O-donor ligands.

PubMed

Huang, Qiu-Ying; Su, Ming-Yang; Meng, Xiang-Ru

2015-06-01

The combination of N-heterocyclic and multicarboxylate ligands is a good choice for the construction of metal-organic frameworks. In the title coordination polymer, poly[bis{μ2-1-[(1H-benzimidazol-2-yl)methyl]-1H-tetrazole-κ(2)N(3):N(4)}(μ4-butanedioato-κ(4)O(1):O(1'):O(4):O(4'))(μ2-butanedioato-κ(2)O(1):O(4))dicadmium], [Cd(C4H4O4)(C9H8N6)]n, each Cd(II) ion exhibits an irregular octahedral CdO4N2 coordination geometry and is coordinated by four O atoms from three carboxylate groups of three succinate (butanedioate) ligands and two N atoms from two 1-[(1H-benzimidazol-2-yl)methyl]-1H-tetrazole (bimt) ligands. Cd(II) ions are connected by two kinds of crystallographically independent succinate ligands to generate a two-dimensional layered structure with bimt ligands located on each side of the layer. Adjacent layers are further connected by hydrogen bonding, leading to a three-dimensional supramolecular architecture in the solid state. Thermogravimetric analysis of the title polymer shows that it is stable up to 529 K and then loses weight from 529 to 918 K, corresponding to the decomposition of the bimt ligands and succinate groups. The polymer exhibits a strong fluorescence emission in the solid state at room temperature.

Synthesis and Characterization of Templated Ion Exchange Resins for the Selective Complexion of Actinide Ions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murrray, George M.; Uy, O. Manuel

The purpose of this research is to develop polymeric extractants for the selective complexation of uranyl ions (and subsequently other actinyl and actinide ions) from aqueous solutions. Selectivity for a specific actinide ion is obtained by providing the polymers with cavities lined with complexing ligands so arranged as to match the charge, coordination number, coordination geometry, and size of the actinide ion. These cavity-containing polymers are produced by using a specific actinide ion (or surrogate) as a template around which monomeric complexing ligands are polymerized. The polymers provide useful sequestering agents for removing actinide ions from wastes and will formmore » the basis for a variety of analytical techniques for actinide determination.« less

Facile synthesis of 2D Zn(II) coordination polymer and its crystal structure, selective removal of methylene blue and molecular simulations

NASA Astrophysics Data System (ADS)

Sezer, Güneş Günay; Yeşilel, Okan Zafer; Şahin, Onur; Arslanoğlu, Hasan; Erucar, İlknur

2017-09-01

A new coordination polymer {[Zn(μ3-ppda)(H2O)(μ-bpa)Zn(μ-ppda)(μ-bpa)]·4H2O}n (1) (ppda = 1,4-phenylenediacetate, bpa = 1,2-bis(4-pyridyl)ethane) has been synthesized by microwave-assisted reaction and characterized by elemental analysis, IR spectroscopy, single-crystal and powder X-ray diffractions. The asymmetric unit of 1 consists of two Zn(II) ions, two bpa ligands, two ppda ligands, one coordinated and four non-coordinated water molecules. In 1, ppda2- anions are linked the adjacent Zn(II) centers to generate 1D double-stranded chains. These chains are connected into 2D sheets by the bridging bpa ligands. Atomically detailed modeling was performed to compute single and binary component adsorption isotherms of H2, CO2, CH4 and N2 in complex 1. Results showed that 1 exhibits a high adsorption selectivity towards CO2 due to its high affinity for CO2. Results of this study will be helpful to guide the microwave-assisted reaction of coordination polymers to design promising adsorbents for gas storage and gas separation applications. The luminescent property of 1 and the selective removal of dyes in 1 have been also discussed. Results showed that 1 can be a potential candidate for luminescence applications and can selectively adsorb methylene blue (MB) dye molecules.

Lanthanide Organophosphate Spiro Polymers: Synthesis, Structure, and Magnetocaloric Effect in the Gadolinium Polymer.

PubMed

Gupta, Sandeep K; Bhat, Gulzar A; Murugavel, Ramaswamy

2017-08-07

Spirocyclic lanthanide organophosphate polymers, {[Ln(dipp)(dippH)(CH 3 OH)(H 2 O) 2 ](CH 3 OH) 2 } n [Ln = La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8), Dy (9), Ho (10), Er (11)], have been prepared from the reaction of Ln(NO 3 ) 3 ·xH 2 O with sterically hindered 2,6-diisopropylphenyl phosphate (dippH 2 ) using aqueous NaOH as the base. The one-dimensional chainlike lanthanide (III) organophosphate coordination polymers have been characterized with the aid of analytical and spectroscopic methods. The single crystal structure determination of polymers (2-5 and 7-11) reveals that in these compounds the hydrophobic organic groups of the phosphate provide a protective coating for the inorganic lanthanide phosphate polymeric chain. The encapsulation of inorganic lanthanide phosphate core, which has very low solubility product, within the organic groups assists in the facile crystallization of the polymers. The di- and monoanionic organophosphate ligands dipp 2- and dippH - display [2.111] and [2.110] binding modes, respectively, in 2-5 and 7. However, they exhibit only [2.110] binding mode in the case of 8-11. This results in the formation of two different types of polymers. While the lighter rare-earth metal ions in 2-5 and 7 display eight coordinate biaugmented trigonal prismatic geometry, the heavier rare-earth metal ions in 9-11 exhibit a seven coordinate capped trigonal prismatic environment. The Tb(III) ion in 8 displays distorted pentagonal bipyramidal geometry. Magnetic studies reveal the presence of weak antiferromagnetic interactions between the Ln(III) ions through the organophosphate ligand. The isotropic Gd(III) polymer 7 exhibits a maximum entropy change of 17.83 J kg -1 K -1 for a field change of 7.0 T at 2.5 K, which is significant considering the high molecular weight of the organophosphate ligand. These polymers represent the first family of any structurally characterized rare-earth organophosphate polymers derived from monoesters of phosphoric acid.

A Sr2+-metal-organic framework with high chemical stability: synthesis, crystal structure and photoluminescence property.

PubMed

Jia, Yan-Yuan; Liu, Xiao-Ting; Wang, Wen-He; Zhang, Li-Zhu; Zhang, Ying-Hui; Bu, Xian-He

2017-01-13

Metal-organic frameworks (MOFs) are typically built by assembly of metal centres and organic linkers, and have emerged as promising crystalline materials in a variety of fields. However, the stability of MOFs is a key limitation for their practical applications. Herein, we report a novel Sr 2+: -MOF [Sr 4 (Tdada) 2 (H 2 O) 3 (DMF) 2 ] (denoted as NKU- 105: , NKU = Nankai University; H 4 Tdada = 5,5'-((thiophene-2,5-dicar bonyl)bis(azanediyl))diisophthalic acid; DMF = N,N-dimethylformamide) featuring an open square channel of about 6 Å along the c-axis. Notably, NKU- 105: exhibits much outstanding chemical stability against common organic solvents, boiling water, acids and bases, relative to most MOF materials. Furthermore, NKU- 105: is an environment-friendly luminescent material with a bright cyan emission.This article is part of the themed issue 'Coordination polymers and metal-organic frameworks: materials by design'. © 2016 The Author(s).

A Sr2+-metal–organic framework with high chemical stability: synthesis, crystal structure and photoluminescence property

PubMed Central

Jia, Yan-Yuan; Liu, Xiao-Ting; Wang, Wen-He; Zhang, Li-Zhu; Bu, Xian-He

2017-01-01

Metal–organic frameworks (MOFs) are typically built by assembly of metal centres and organic linkers, and have emerged as promising crystalline materials in a variety of fields. However, the stability of MOFs is a key limitation for their practical applications. Herein, we report a novel Sr2+-MOF [Sr4(Tdada)2(H2O)3(DMF)2] (denoted as NKU-105, NKU = Nankai University; H4Tdada = 5,5'-((thiophene-2,5-dicar bonyl)bis(azanediyl))diisophthalic acid; DMF = N,N-dimethylformamide) featuring an open square channel of about 6 Å along the c-axis. Notably, NKU-105 exhibits much outstanding chemical stability against common organic solvents, boiling water, acids and bases, relative to most MOF materials. Furthermore, NKU-105 is an environment-friendly luminescent material with a bright cyan emission. This article is part of the themed issue ‘Coordination polymers and metal–organic frameworks: materials by design’. PMID:27895256

Metal-Organic Framework-Polymer Composite as a Highly Efficient Sorbent for Sulfonamide Adsorption and Desorption: Effect of Coordinatively Unsaturated Metal Site and Topology.

PubMed

Shih, Yung-Han; Wang, Kuen-Yun; Singco, Brenda; Lin, Chia-Her; Huang, Hsi-Ya

2016-11-08

In this study, we first demonstrated the effect of two types of metal-organic framework-polymer (MOF-polymer) monoliths on in-tube solid-phase microextraction (IT-SPME) of sulfonamides. Sulfonamides were successfully adsorbed onto MIL-101(Cr)-polymer but were difficult to elute due to these sulfonamides could interact via Lewis acid-base interaction with the presence of Cr(III) coordinatively unsaturated metal sites (CUS). Moreover, the cage-type topology of MIL-101(Cr) that could produce multiple pathways thus complicates the desorption of the test analytes from the sorbent. Contrastingly, MIL-53(Al)-polymer provided weaker Al(III) CUS, and its one-dimensional channel pore structure could provide an unhindered pathway for sulfonamides transfer during elution. After optimizing the IT-SPME condition such as MOF content, pH of sample matrix, column length, extraction flow rate, and elution volume, the calculated extraction recovery of sulfonamides in MIL-53(Al)-polymer as analyzed by microemulsion electrokinetic chromatography (MEEKC) were in the range of 40%-90% with relative standard deviations (RSDs) below 5% and a reusability of at least 30 times.

Polymers and Cross-Linking: A CORE Experiment to Help Students Think on the Submicroscopic Level

ERIC Educational Resources Information Center

Bruce, Mitchell R. M.; Bruce, Alice E.; Avargil, Shirly; Amar, Francois G.; Wemyss, Thomas M.; Flood, Virginia J.

2016-01-01

The Polymers and Cross-Linking experiment is presented via a new three phase learning cycle: CORE (Chemical Observations, Representations, Experimentation), which is designed to model productive chemical inquiry and to promote a deeper understanding about the chemistry operating at the submicroscopic level. The experiment is built on two familiar…

Chiral zinc phenylalanine nanofibers with fluorescence.

PubMed

Chen, Erdan; Guo, Beidou; Zhang, Baohong; Gan, Li-Hua; Gong, Jian Ru

2011-09-01

Chiral Zn(II)/D-,L-phenylalanine (Phe) bio-coordination polymer nanofibers with fluorescence were prepared by fast coordination-assisted assembly. The synthetic strategy is based on the fact that the Zn2+ ions were linked to oxygen atoms from carboxylate groups of the D- or L-amino acid by coordination interactions to form the chiral polymers. The Zn(II)/D-,L-Phe nanofibers had homogeneous diameters in the range of 700-900 nm and ultra-long length in several hundred micrometers, and the surface of the fiber was extremely smooth. In addition, the enantiomers of Zn(II)/Phe nanofibers exhibited both optical activity and fluorescent property in the solid state, which has great potential for application in the field of biomimetic nanofabrication and micro-/nano-optoelectronics.

catena-Poly[[triphenyl-tin(IV)]-μ-phenyl-phosphinato-κO:O'].

PubMed

Diop, Tidiane; Diop, Libasse; Kociok-Köhn, Gabriele; Molloy, Kieran C; Stoeckli-Evans, Helen

2011-12-01

In the structure of the title coordination polymer, [Sn(C(6)H(5))(3)(C(6)H(6)O(2)P)](n) or [PhP(H)O(2)Sn(IV)(Ph)(3)](n), the Sn(IV) atom is five-coordinate, with the SnC(3)O(2) framework in a trans trigonal-bipyramidal arrangement having the PhP(H)O(2) (-) anions in apical positions. In the crystal, neighbouring polymer chains are linked via C-H⋯π inter-actions, forming a two-dimensional network lying parallel to (001).

Coordination polymers of 5-substituted isophthalic acid

DOE PAGES

McCormick, Laura J.; Morris, Samuel A.; Slawin, Alexandra M. Z.; ...

2015-12-10

In this work, the synthesis and characterisation of five coordination polymers - Ni 2(mip) 2 (H 2O) 8 ·2H 2O (1), Zn 6(mip) 5(OH) 2(H 2O) 4 ·7.4H 2O (2), Zn 6(mip) 5(OH) 2(H 2O) 2 ·4H 2O (3), Mn(HMeOip) 2 (4), and Mn 3(tbip) 2(Htbip) 2(EtOH) 2 (5) - are reported. Preliminary nitric oxide release data on compounds 2 and 3 are also given.

Supramolecular polymeric chemosensor for biomedical applications: design and synthesis of a luminescent zinc metallopolymer as a chemosensor for adenine detection.

PubMed

Chow, Cheuk-Fai

2012-11-01

Adenine is an important bio-molecule that plays many crucial roles in food safety and biomedical diagnostics. Differentiating adenine from a mixture of adenosine and other nucleic bases (guanine, thymine, cytosine, and uracil) is particularly important for both biological and clinical applications. A neutral Zn(II) metallosupramolecular polymer based on acyl hydrazone derived coordination centres (P1) were generated through self-assembly polymerization. It is a linear coordination polymer that behaves like self-standing film. The synthesis, (1)H-NMR characterization, and spectroscopic properties of this supramolecular material are reported. P1 was found to be a chemosensor specific to adenine, with a luminescent enhancement. The binding properties of P1 with common nucleic bases and nucleosides reveal that this supramolecular polymer is very selective to adenine molecules (~20 to 420 times more selectivity than other nucleic bases). The formation constant (K) of P1 to adenine was found to be log K = 4.10 ± 0.02. This polymeric chemosensor produces a specific response to adenine down to 90 ppb. Spectrofluorimetric and (1)H-NMR titration studies showed that the P1 polymer allows each Zn(II) coordination centre to bind to two adenine molecules through hydrogen bonding with their imine and hydrazone protons.

Selective high capacity adsorption of Congo red, luminescence and antibacterial assessment of two new cadmium(II) coordination polymers

NASA Astrophysics Data System (ADS)

Beheshti, Azizolla; Nozarian, Kimia; Ghamari, Narges; Mayer, Peter; Motamedi, Hossein

2018-02-01

Coordination polymers [CdCl(NCS)L]n (1) and {[Cd2I4(L)2]·H2O·DMF}n (2) (where L = 1, 1-(1,4-butanediyl)bis(1,3-dihydro-3-methyl-1H-imidazole- 2-thione)) were synthesized and structurally characterized. Compounds 1 and 2 both possess a tetrahedral arrangement with CdS2NCl and CdS2I2 cores, respectively. In these structures, the flexible thione ligands adopt a μ- bridging coordination mode to form 1D chains along the b-axis. The 1D chains are join together by C-H--Cl hydrogen bonds (in 1) and water molecules (in 2) to create a 2D supramolecular framework with an ABAB…packing mode. Remarkably, compounds 1 and 2 in particular polymer 1 exhibit excellent capacity to adsorb Congo red (CR) with high selectivity. The experimental data demonstrate that the mechanism of sorption process can be described by the Elovich and pseudo second order kinetic models for 1 and 2, respectively. Furthermore, the possible mechanism of CR absorption was investigated by UV-Vis and solid state fluorescence spectra for the title polymers. In addition, the antibacterial assessment of these compounds have also been studied.

Cadmium-1,4-cyclohexanedicarboxylato coordination polymers bearing different di-alkyl-2,2'-bipyridines: syntheses, crystal structures and photoluminescence studies.

PubMed

Rosales-Vázquez, Luis D; Sánchez-Mendieta, Víctor; Dorazco-González, Alejandro; Martínez-Otero, Diego; García-Orozco, Iván; Morales-Luckie, Raúl A; Jaramillo-Garcia, Jonathan; Téllez-López, Antonio

2017-09-26

Four coordination polymers have been synthesized using self-assembly solution reactions under ambient conditions, reacting Cd(ii) ions with 1,4-cyclohexanedicarboxylic acid in the presence of different 2,2'-bipyridine co-ligands: {[Cd(H 2 O)(e,a-cis-1,4-chdc)(2,2'-bpy)]·H 2 O} n (1); [Cd 2 (H 2 O) 2 (e,a-cis-1,4-chdc) 2 (4,4'-dmb) 2 ] n (2); {[Cd(e,a-cis-1,4-chdc)(5,5'-dmb)]·H 2 O·CH 3 OH} n (3) and {[Cd(e,e-trans-1,4-chdc)(4,4'-dtbb)]·CH 3 OH} n (4), where 1,4-chdc = 1,4-cyclohexanedicarboxylato, 2,2'-bpy = 2,2'-bipyridine, 4,4'-dmb = 4,4'-dimethyl-2,2'-bipyridine, 5,5'-dmb = 5,5'-dimethyl-2,2'-bipyridine and 4,4'-dtbb = 4,4'-di-tert-butyl-2,2'-bipyridine. Crystallographic studies show that compound 1 has a 1D structure propagating along the crystallographic b-axis; the Cd ion in 1 is six-coordinated with a distorted-octahedral coordination sphere. Compound 2 has two crystallographic different Cd ions and both are six-coordinated with a distorted-octahedral coordination sphere. Compound 3 exhibits a seven-coordinated Cd ion having a distinctive distorted-monocapped trigonal prismatic geometry. In compound 4, the Cd ion is also seven-coordinated in a distorted monocapped octahedral geometry. Compounds 2, 3 and 4 possess rhombic-shaped dinuclear units (Cd 2 O 2 ) as nodes to generate larger cycles made up of four dinuclear units, a Cd 4 motif, bridged by four 1,4-chdc ligands, accomplishing, thus, 2D structures. Remarkably, in compound 4 the 1,4-chdc ligand conformation changes to the equatorial, equatorial trans, unlike the other compounds where the bridging ligand conformation is the more typical equatorial, axial cis. The solid state luminescence properties of 1-4 were investigated; polymers 3 and 4 exhibited a strong blue emission (λ em = 410-414 nm) compared to 1 and 2; structure-related photoluminescence is attributed to the degree of hydration of the compounds. Furthermore, Cd-polymer 3 suspended in acetone allows the fluorescence selective sensing of acetonitrile over common organic solvents such as alcohols and DMF, based on turn-on fluorescence intensity with a limit of 53 μmol L -1 .

Spontaneous aggregation of lithium ion coordination polymers in fluorinated electrolytes for high-voltage batteries

DOE PAGES

Malliakas, Christos D.; Leung, Kevin; Pupek, Krzysztof Z.; ...

2016-03-31

Fluorinated carbonate solvents are pursued as liquid electrolytes for high-voltage Li-ion batteries. We report aggregation of [Li +(FEC) 3] n polymer species from fluoroethylene carbonate containing electrolytes and scrutinized the causes for this behavior.

Developing a Suitable Model for Water Uptake for Biodegradable Polymers Using Small Training Sets.

PubMed

Valenzuela, Loreto M; Knight, Doyle D; Kohn, Joachim

2016-01-01

Prediction of the dynamic properties of water uptake across polymer libraries can accelerate polymer selection for a specific application. We first built semiempirical models using Artificial Neural Networks and all water uptake data, as individual input. These models give very good correlations (R (2) > 0.78 for test set) but very low accuracy on cross-validation sets (less than 19% of experimental points within experimental error). Instead, using consolidated parameters like equilibrium water uptake a good model is obtained (R (2) = 0.78 for test set), with accurate predictions for 50% of tested polymers. The semiempirical model was applied to the 56-polymer library of L-tyrosine-derived polyarylates, identifying groups of polymers that are likely to satisfy design criteria for water uptake. This research demonstrates that a surrogate modeling effort can reduce the number of polymers that must be synthesized and characterized to identify an appropriate polymer that meets certain performance criteria.

The influence of pore structure parameters on the digital core recovery degree

NASA Astrophysics Data System (ADS)

Xia, Huifen; Zhao, Ling; Sun, Yanyu; Yuan, Shi

2017-05-01

Constructing digital core in the research of water flooding or polymer flooding oil displacement efficiency has its unique advantage. Using mercury injection experiment measured pore throat size distribution frequency, coordination number measured by CT scanning method and imbibition displacement method is used to measure the wettability of the data, on the basis of considering pore throat ratio, wettability, using the principle of adaptive porosity, on the basis of fitting the permeability to complete the construction of digital core. The results show that the model of throat distribution is concentrated water flooding recovery degree is higher, and distribution is more decentralized model polymer flooding recovery degree is higher. Around the same number of PV in poly, coordination number model of water flooding and polymer flooding recovery degree is higher.

Photoluminescent lead(II) coordination polymers stabilised by bifunctional organoarsonate ligands

NASA Astrophysics Data System (ADS)

Lin, Jian-Di; Onet, Camelia I.; Schmitt, Wolfgang

2015-04-01

Four lead(II) coordination polymers were isolated under hydro(solvo)thermal conditions. The applied synthetic methodology takes advantage of the coordination behaviour of a new bifunctional organoarsonate ligand, 4-(1, 2, 4-triazol-4-yl)phenylarsonic acid (H2TPAA) and involves the variation of lead(II) reactants, metal/ligand mole ratios, and solvents. The constitutional composition of the four lead(II) coordination polymers can be formulated as [Pb2(TPAA)(HTPAA)(NO3)]·6H2O (1), [Pb2(TPAA)(HTPAA)2]·DMF·0.5H2O (DMF = N, N-Dimethylformamide) (2), [Pb2Cl2(TPAA)H2O] (3), and [Pb3Cl(TPAA)(HTPAA)2H2O]Cl (4). The compounds were characterized by single-crystal and powder x-ray diffraction techniques, thermogravimetric analyses, infra-red spectroscopy, and elemental analyses. Single-crystal x-ray diffraction reveals that 1 and 2 represent two-dimensional (2D) layered structures whilst 3 and 4 form three-dimensional (3D) frameworks. The structures of 1, 2, and 4 contain one-dimensional (1D) {PbII/AsO3} substructures, while 3 is composed of 2D {PbII/AsO3} arrays. Besides their interesting topologies, 1-4 all exhibit photoluminescence properties in the solid state at room temperature.

Co-assembly of Zn(SPh){sub 2} and organic linkers into helical and zig-zag polymer chains

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu Yi; Yu Lingmin; Loo, Say Chye Joachim

2012-07-15

Two novel one-dimensional coordination polymers, single helicate [Zn(SPh){sub 2}(TPyTA)(EG)]{sub n} (EG=ethylene glycol) (1) and zig-zag structure [Zn(SPh){sub 2}(BPyVB)]{sub n} (2), were synthesized under solvothermal conditions at 150 Degree-Sign C or room temperature by the co-assembly of Zn(SPh){sub 2} and organic linkers such as 2,4,6-tri(4-pyridyl)-1,3,5-triazine (TPyTA) and 1,3-bis(trans-4-pyridylvinyl)benzene (BPyVB). X-ray crystallography study reveals that both polymers 1 and 2 crystallize in space group P2{sub 1}/c of the monoclinic system. The solid-state UV-vis absorption spectra show that 1 and 2 have maxium absorption onsets at 400 nm and 420 nm, respectively. TGA analysis indicates that 1 and 2 are stable up tomore » 110 Degree-Sign C and 210 Degree-Sign C. - Graphical abstract: Two novel one-dimensional coordination polymers, single helicate [Zn(SPh){sub 2}(TPyTA)(EG)]{sub n} (1) and zig-zag structure [Zn(SPh){sub 2}(BPyVB)]{sub n} (2), were synthesized. Solid-state UV-vis absorptions show that 1 and 2 have maxium absorption onsets at 400 nm and 420 nm, respectively. TGA analysis indicates that 1 and 2 are stable up to 110 Degree-Sign C and 210 Degree-Sign C. Highlights: Black-Right-Pointing-Pointer Two novel one-dimensional coordination polymers have been synthesized. Black-Right-Pointing-Pointer TPyTA results in helical structures in 1 while BPyVB leads to zig-zag chains in 2. Black-Right-Pointing-Pointer Solid-state UV-vis absorption spectra and TGA analysis of the title polymers were studied.« less

Ligand-controlled assembly of Cd(II) coordination polymers based on mixed ligands of naphthalene-dicarboxylate and dipyrido[3,2-d:2‧,3‧-f]quinoxaline: From 0D+1D cocrystal, 2D rectangular network (4,4), to 3D PtS-type architecture

NASA Astrophysics Data System (ADS)

Liu, Guocheng; Chen, Yongqiang; Wang, Xiuli; Chen, Baokuan; Lin, Hongyan

2009-03-01

Three novel Cd(II) coordination polymers, namely, [Cd(Dpq)(1,8-NDC)(H 2O) 2][Cd(Dpq)(1,8-NDC)]·2H 2O ( 1), [Cd(Dpq)(1,4-NDC)(H 2O)] ( 2), and [Cd(Dpq)(2,6-NDC)] ( 3) have been obtained from hydrothermal reactions of cadmium(II) nitrate with the mixed ligands dipyrido [3,2-d:2',3'-f]quinoxaline (Dpq) and three structurally related naphthalene-dicarboxylate ligands [1,8-naphthalene-dicarboxylic acid (1,8-H 2NDC), 1,4-naphthalene-dicarboxylic acid (1,4-H 2NDC), and 2,6-naphthalene-dicarboxylic acid (2,6-H 2NDC)]. Single-crystal X-ray diffraction analysis reveals that the three polymers exhibit novel structures due to different naphthalene-dicarboxylic acid. Compound 1 is a novel cocrystal of left- and right-handed helical chains and binuclear complexes and ultimately packed into a 3D supramolecular structure through hydrogen bonds and π- π stacking interactions. Compound 2 shows a 2D rectangular network (4,4) bridged by 1,4-NDC with two kinds of coordination modes and ultimately packed into a 3D supramolecular structure through inter-layer π- π stacking interactions. Compound 3 is a new 3D coordination polymer with distorted PtS-type network. In addition, the title compounds exhibit blue/green emission in solid state at room temperature.

Spacecraft dielectric material properties and spacecraft charging

NASA Technical Reports Server (NTRS)

Frederickson, A. R.; Wall, J. A.; Cotts, D. B.; Bouquet, F. L.

1986-01-01

The physics of spacecraft charging is reviewed, and criteria for selecting and testing semiinsulating polymers (SIPs) to avoid charging are discussed and illustrated. Chapters are devoted to the required properties of dielectric materials, the charging process, discharge-pulse phenomena, design for minimum pulse size, design to prevent pulses, conduction in polymers, evaluation of SIPs that might prevent spacecraft charging, and the general response of dielectrics to space radiation. SIPs characterized include polyimides, fluorocarbons, thermoplastic polyesters, poly(alkanes), vinyl polymers and acrylates, polymers containing phthalocyanine, polyacene quinones, coordination polymers containing metal ions, conjugated-backbone polymers, and 'metallic' conducting polymers. Tables summarizing the results of SIP radiation tests (such as those performed for the NASA Galileo Project) are included.

Four coordination polymers based on 5-tert-butyl isophthalic acid and rigid bis(imidazol-1yl)benzene linkers: Synthesis, luminescence detection of acetone and optical properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arıcı, Mürsel, E-mail: marici@ogu.edu.tr; Zafer Yeşilel, Okan; Büyükgüngör, Orhan

Four coordination polymers including, [Co(µ-Htbip){sub 2}(µ-dib)]{sub n} (1), [Co(µ-tbip)(µ-dmib){sub 0.5}]{sub n} (2), [Zn{sub 2}(µ-tbip)(µ{sub 3}-tbip)(µ-dmib){sub 1.5}]{sub n} (3) and [Cd(µ{sub 3}-tbip)(µ-dib){sub 0.5} (H{sub 2}O)]{sub n} (4) (tbip: 5-tert-butylisophthalate, dib: 1,4-bis(imidazol-1yl)benzene, dmib: 1,4-bis(imidazol-1yl)-2,5-dimethylbenzene), were hydrothermally synthesized and characterized by elemental analysis, IR spectra, single crystal and powder X-ray diffraction and thermal analysis (TG/DTA). The structural diversity is observed depending on ligands and coordination number of metal centers in the synthesized complexes. The tbip ligand displayed five different coordination modes in its complexes. In 1 and 2, complex 1 is 3D framework with the dia topology while complex 2 has 2D structuremore » with the sql topology depending on coordination geometries of Co ions. Complex 3 is 3D framework with the fsh 4,6-conn topology and complex 4 has 2D 4-connected sql topology. Photoluminescent properties of complex 3 dispersed in various organic solvents were investigated and the results showed that 3 dispersed in methanol could be used as a fluorescent sensor for the detection of acetone. Moreover, thermal and optical properties of the complexes were also studied. - Graphical abstract: Four coordination polymers were hydrothermally synthesized and characterized by various techniques. The complexes showed the structural diversity depending on ligands and coordination number of metal centers. The tbip ligand displayed four different coordination modes in its complexes. In 1 and 2, complexes 1 and 2 are 3D and 2D structures with the dia and sql topologies depending on coordination geometries of Co ions, respectively. Complexes 3 and 4 are 3D and 2D structures with the fsh 4,6-conn and sql topology, respectively. Photoluminescent properties of complex 3 dispersed in various organic solvents were investigated and the results showed that 3 dispersed in methanol could be used as a fluorescent sensor for the detection of acetone. Moreover, thermal and optical properties of the complexes were also studied. - Highlights: • Four new 2D and 3D coordination polymers with 5-tert-butyl isophthalic acid and rigid bis(imidazol-1yl)benzene linkers. • The structural diversity depending on ligands and coordination number of metal centers. • Fluorescent sensor for the detection of acetone.« less

1D helical cadmium coordination polymers containing hydrazide ligand: The role of solvent and molar ratio

NASA Astrophysics Data System (ADS)

Notash, Behrouz

2018-03-01

Three new cadmium coordination polymers, [Cd(L)(NO3)2CH3OH]n, 1, {[Cd(L)2(NO3)]NO3}n, 2 and {[Cd(L)2(NO3)]NO3.H2O}n3, which L is nicotinohydrazide have been synthesized and characterized by spectroscopic methods as well as single crystal X-ray diffraction. Compounds 1-3 have been synthesized by changing solvent and metal-to-ligand ratio. X-ray crystallography showed that compounds 1-3 have different 1D helical structural motif. Semi-flexible nature of L ligand causes to syn-syn conformation which leading to form 1D helical chains coordination polymers. Compounds 2 and 3 were synthesized under the same reaction conditions with similar molar ratio, but using different solvent system. These compounds are pseudopolymorph which differs in the presence or absence of water molecule in their crystal packing. Hirshfeld surface analysis of the structures 1-3 have been performed and find the percent of participation of intermolecular interactions in the crystal packing of compounds.

Crystal structure of catena-poly[[aquadi-n-propyl­tin(IV)]-μ-oxalato

PubMed Central

Reichelt, Martin; Reuter, Hans

2014-01-01

The title compound, [Sn(C3H7)2(H2O)(C2O4)]n, represents the first diorganotin(IV) oxalate hydrate to be structurally characterized. The tin(IV) atom of the one-dimensional coordination polymer is located on a twofold rotation axis and is coordinated by two chelating oxalate ligands with two slightly different Sn—O bond lengths of 2.290 (2) and 2.365 (2) Å, two symmetry-related n-propyl groups with a Sn—C bond lengths of 2.127 (3) Å, and a water mol­ecule with a Sn—O bond length of 2.262 (2) Å. The coordination polyhedron around the SnIV atom is a slightly distorted penta­gonal bipyramid with a nearly linear axis between the trans-oriented n-propyl groups [C—Sn—C = 176.8 (1)°]. The bond angles between the oxygen atoms of the equatorial plane range from 70.48 (6)° to 76.12 (8)°. A one-dimensional coordination polymer results from the less asymmetric bilateral coordination of the centrosymmetric oxalate anion, inter­nally reflected by two slightly different C—O bond lengths of 1.248 (3) and 1.254 (3) Å. The chains of the polymer propagate parallel to [001] and are held together by hydrogen bonds between water mol­ecules and oxalate anions of neighboring chains, leading to a two-dimensional network parallel to (100). PMID:25249862

N-(sulfoethyl) iminodiacetic acid-based lanthanide coordination polymers: Synthesis, magnetism and quantum Monte Carlo studies

NASA Astrophysics Data System (ADS)

Zhuang, Gui-lin; Chen, Wu-lin; Zheng, Jun; Yu, Hui-you; Wang, Jian-guo

2012-08-01

A series of lanthanide coordination polymers have been obtained through the hydrothermal reaction of N-(sulfoethyl) iminodiacetic acid (H3SIDA) and Ln(NO3)3 (Ln=La, 1; Pr, 2; Nd, 3; Gd, 4). Crystal structure analysis exhibits that lanthanide ions affect the coordination number, bond length and dimension of compounds 1-4, which reveal that their structure diversity can be attributed to the effect of lanthanide contraction. Furthermore, the combination of magnetic measure with quantum Monte Carlo(QMC) studies exhibits that the coupling parameters between two adjacent Gd3+ ions for anti-anti and syn-anti carboxylate bridges are -1.0×10-3 and -5.0×10-3 cm-1, respectively, which reveals weak antiferromagnetic interaction in 4.

Coordination polymer flexibility leads to polymorphism and enables a crystalline solid-vapour reaction: a multi-technique mechanistic study.

PubMed

Vitórica-Yrezábal, Iñigo J; Libri, Stefano; Loader, Jason R; Mínguez Espallargas, Guillermo; Hippler, Michael; Fletcher, Ashleigh J; Thompson, Stephen P; Warren, John E; Musumeci, Daniele; Ward, Michael D; Brammer, Lee

2015-06-08

Despite an absence of conventional porosity, the 1D coordination polymer [Ag4 (O2 C(CF2 )2 CF3 )4 (TMP)3 ] (1; TMP=tetramethylpyrazine) can absorb small alcohols from the vapour phase, which insert into AgO bonds to yield coordination polymers [Ag4 (O2 C(CF2 )2 CF3 )4 (TMP)3 (ROH)2 ] (1-ROH; R=Me, Et, iPr). The reactions are reversible single-crystal-to-single-crystal transformations. Vapour-solid equilibria have been examined by gas-phase IR spectroscopy (K=5.68(9)×10(-5) (MeOH), 9.5(3)×10(-6) (EtOH), 6.14(5)×10(-5) (iPrOH) at 295 K, 1 bar). Thermal analyses (TGA, DSC) have enabled quantitative comparison of two-step reactions 1-ROH→1→2, in which 2 is the 2D coordination polymer [Ag4 (O2 C(CF2 )2 CF3 )4 (TMP)2 ] formed by loss of TMP ligands exclusively from singly-bridging sites. Four polymorphic forms of 1 (1-A(LT) , 1-A(HT) , 1-B(LT) and 1-B(HT) ; HT=high temperature, LT=low temperature) have been identified crystallographically. In situ powder X-ray diffraction (PXRD) studies of the 1-ROH→1→2 transformations indicate the role of the HT polymorphs in these reactions. The structural relationship between polymorphs, involving changes in conformation of perfluoroalkyl chains and a change in orientation of entire polymers (A versus B forms), suggests a mechanism for the observed reactions and a pathway for guest transport within the fluorous layers. Consistent with this pathway, optical microscopy and AFM studies on single crystals of 1-MeOH/1-A(HT) show that cracks parallel to the layers of interdigitated perfluoroalkyl chains develop during the MeOH release/uptake process. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A new (4, 6)-connected Cu(I) coordination polymer based on rare tetranuclear [Cu4I2] clusters: Synthesis, crystal structure, luminescent and photocatalytic properties

NASA Astrophysics Data System (ADS)

Cui, Li-Jing; Liu, Chun-Yan; Bian, Ming; Yu, Li-Jun

2018-03-01

A new Cu(I) coordination polymer, namely [Cu5I3(L)2]n (1 HL = 3-(4-pyridyl)-5-(3-pyridyl)-1,2,4-triazolyl), was solvothermally synthesized using CuI, HL and NaI as the starting materials. Single crystal X-ray structural analysis shows that compound 1 features a (4, 6)-connected 3D framework employing rare tetranuclear [Cu4I2] clusters as building subunits. It exhibits intense metal-to-ligand luminescence and excellent photocatalytic activity on degradation of methylene blue (MB).

Construction of (CuX)2n cluster-containing (X = Br, I; n = 1, 2) coordination polymers assembled by dithioethers ArS(CH2)(m)SAr (Ar = Ph, p-Tol; m = 3, 5): effect of the spacer length, aryl group, and metal-to-ligand ratio on the dimensionality, cluster nuclearity, and the luminescence properties of the metal-organic frameworks.

PubMed

Knorr, Michael; Guyon, Fabrice; Khatyr, Abderrahim; Strohmann, Carsten; Allain, Magali; Aly, Shawkat M; Lapprand, Antony; Fortin, Daniel; Harvey, Pierre D

2012-09-17

Reaction of CuI with bis(phenylthio)propane in a 1:1 ratio yields the two-dimensional coordination polymer [{Cu(μ(2)-I)(2)Cu}{μ-PhS(CH(2))(3)SPh}(2)](n) (1). The 2D-sheet structure of 1 is built up by dimeric Cu(2)I(2) units, which are connected via four bridging 1,3-bis(phenylthio)propane ligands. In contrast, treatment of 2 equiv of CuI with 1,3-bis(phenylthio)propane in MeCN solution affords in a self-assembly reaction the strongly luminescent metal-organic 2D-coordination polymer [Cu(4)I(4){μ-PhS(CH(2))(3)Ph}(2)](n) (2), in which cubane-like Cu(4)(μ(3)-I)(4) cluster units are linked by the dithioether ligands. The crystallographically characterized one-dimensional (1D) compound [{Cu(μ(2)-Br)(2)Cu}{μ-PhS(CH(2))(3)SPh}(2)](n) (3) is obtained using CuBr. The outcome of the reaction of PhS(CH(2))(5)SPh with CuI also depends of the metal-to-ligand ratio employed. Mixing CuI and the dithioether in a 2:1 ratio results in formation of [Cu(4)I(4){μ-PhS(CH(2))(5)Ph}(2)](n) (4) in which cubane-like Cu(4)(μ(3)-I)(4) clusters are linked by the bridging dithioether ligand giving rise to a 1D necklace structure. A ribbon-like 1D-polymer with composition [{Cu(μ(2)-I)(2)Cu}{μ-PhS(CH(2))(5)SPh}(2)](n) (5), incorporating rhomboid Cu(2)I(2) units, is produced upon treatment of CuI with 1,5-bis(phenylthio)pentane in a 1:1 ratio. Reaction of CuBr with PhS(CH(2))(5)SPh produces the isomorphous 1D-compound [{Cu(μ(2)-Br)(2)Cu}{μ-PhS(CH(2))(5)SPh}(2)](n) (6). Strongly luminescent [Cu(4)I(4){μ-p-TolS(CH(2))(5)STol-p}(2)](n) (7) is obtained after mixing 1,5-bis(p-tolylthio)pentane with CuI in a 1:2 ratio, and the 2D-polymer [{Cu(μ(2)-I)(2)Cu}(2){μ-p-TolS(CH(2))(5)STol-p}(2)](n) (8) results from reaction in a 1:1 metal-to-ligand ratio. Under the same reaction conditions, 1D-polymeric [{Cu(μ(2)-Br)(2)Cu}{μ-p-TolS(CH(2))(5)STol-p}(2)](n) (9) is formed using CuBr. This study reveals that the structure of the self-assembly process between CuX and ArS(CH(2))(m)SAr ligands is hard to predict. The solid-state luminescence spectra at 298 and 77 K of 2 and 4 exhibit very strong emissions around 535 and 560 nm, respectively, whereas those for 1 and 5 display weaker ones at about 450 nm. The emission lifetimes are longer for the longer wavelength emissions (>1.0 μs arising from the cubane species) and shorter for the shorter wavelength ones (<1.4 μs arising from the rhomboid units). The Br-containing species are found to be weakly fluorescent.

2-(hydroxymethyl)-1H-benzo[d]imidazole-5-carboxylic acid as linker for Co(II)/Ni(II)/Cu(II) coordination polymers: Synthesis, structures and properties

NASA Astrophysics Data System (ADS)

Wang, Duo-Zhi; Wang, Xin-Fang; Du, Jia-Qiang; Dong, Jun-Liang; Xie, Fei

2018-02-01

We report the synthesis and characterization of five transition metal coordination polymers (CPs) based on M(II) (M: Co, Ni and Cu), 2-(hydroxymethyl)-1H-benzo[d]imidazole-5-carboxylic acid (H2L) ligand. They are formulated as {[Co2(HL)2(H2O)3(SO4)]·H2O}n (1), {[Co2(HL)2(H2O)2]·SiF6}n (2), {[Ni2(HL)2(H2O)3(SO4)]·2H2O}n (3), {[Ni2(HL)2(H2O)4]·H2O·SiF6}n (4), {[Cu2(HL)2(H2O)2]·SiF6}n (5). The complexes 1-5 structure were characterized by single-crystal X-ray diffraction, elemental analyses, infrared spectroscopy (IR), powder X-ray diffraction (PXRD), and thermogravimetric analyses (TGA). Complexes 1-5 are two-dimensional (2D) network type coordination polymers that 1-3, 5 crystallize in monoclinic system within the centrosymmetric space group P2(1)/c, and 4 in triclinic system P-1 space group, they show the same coordination modes (κ1-κ1)-(κ1)-(κ1)-μ3 in coordination polymers. Complexes 1 and 3 expand to three-dimensional framework by means of hydrogen bond interactions, and can be rationalized to be three-connected {63} topological network, while 2, 4, 5 exhibit the topological network with a four-connected {44·62} topological sql network. The luminescent properties (for complexes 1, 2) and UV diffuse reflectance (for complexes 1-5) in the solid state at room temperature were also investigated and discussed. Complexes 1-5 act as effective heterogeneous catalysts, under mild conditions, for the homocoupling reaction of 4-substituted aryl iodides bearing electron-donating groups (-CH3, -OCH3).

Coordination Polymers Derived from Non-Steroidal Anti-Inflammatory Drugs for Cell Imaging and Drug Delivery.

PubMed

Paul, Mithun; Dastidar, Parthasarathi

2016-01-18

A new series of Mn(II) coordination polymers, namely, [{Mn(L)(H2 O)2 }⋅2 Nap]∞ (CP1), [{Mn(L)(Ibu)2 (H2 O)2 }]∞ (CP2), [{Mn(L)(Flr)2 (H2 O)2 }]∞ (CP3), [{Mn(L)(Ind)2 (H2 O)2 }⋅H2 O]∞ (CP4), [{Mn2 (L)2 (μ-Flu)4 (H2 O)}⋅L]∞ (CP5), [{Mn2 (L)2 (μ-Tol)4 (H2 O)2 }]∞ (CP6) and [{Mn2 (L)2 (μ-Mef)4 (H2 O)2 }]∞ (CP7) (Nap=naproxen, Ibu=ibuprofen, Flr=flurbiprofen, Ind=indometacin, Flu=flufenamic acid, Tol=tolfenamic acid and Mef=mefenamic acid) derived from various non-steroidal anti-inflammatory drugs (NSAIDs) and the organic linker 1,2-bis(4-pyridyl)ethylene (L) have been synthesized with the aim of being used for cell imaging and drug delivery. Single-crystal X-ray diffraction (SXRD) studies revealed that the NSAID molecules were part of the coordination polymeric network either through coordination to the metal center (in the majority of the cases) or through hydrogen bonding. Remarkably, all the Mn(II) coordination polymers were found to be soluble in DMSO, thereby making them particularly suitable for the desired biological applications. Two of the coordination polymers (namely, CP1 and CP3) reported herein, were found to be photoluminescent both in the solid as well as in the solution state. Subsequent experiments (namely, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), and PGE2 (prostaglandin E2 ) assays) established their biocompatibility and anti-inflammatory response. In vitro studies by using a macrophage cell line (i.e., RAW 264.7) revealed that both CP1 and CP3 were excellent cell imaging agents. Finally, biodegradability studies under simulated physiological conditions in phosphate-buffered saline (PBS) at pH 7.6 showed that slow and sustained release of the corresponding NSAID was indeed possible from both CP1 and CP3. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Ya-Jing; Zheng, Yue-Qing, E-mail: zhengyueqing@nbu.edu.cn; Wang, Jin-Jian

A new bismuth-based polymer, [Hbpe][Bi(Hpydc){sub 2}(pydc)]·H{sub 2}O (H{sub 2}pydc=pyridine-2,5-dicarboxylic acid, bpe=trans-bis(4-pyridyl) ethylene) has been hydrothermally synthesized. Transient photocurrent response and electrochemical impedance spectroscopy studies indicate that the synthesized polymer with efficient charge separation and transportation can be used as a potential photocatalyst. So we use it for the degradation of rhodamine B (RhB) dye wastewater under visible light. The comparative study on commercial Bi{sub 2}O{sub 3} shows [Hbpe][Bi(Hpydc){sub 2}(pydc)]·H{sub 2}O has the higher photocatalytic performance, with the degradation rate of 97% and 2% within 100 min for [Hbpe][Bi(Hpydc){sub 2}(pydc)]·H{sub 2}O and commercial Bi{sub 2}O{sub 3} respectively. Additionally, the five cyclemore » reproducibility results of [Hbpe][Bi(Hpydc){sub 2}(pydc)]·H{sub 2}O implies that it can be used as a stable photocatalyst. - Graphical abstract: We report a new 1D coordination polymer [Hbpe][Bi(Hpydc){sub 2}(pydc)]·H{sub 2}O by a facile hydrothermal method. The Bi-CP shows good photoelectric property and photocatalytic activity for RhB degradation under visible white LED lamp irradiation. And the stability of the visible-light-responsive bismuth-based coordination polymer has also been examined. - Highlights: • A new Bi(III) coordination polymer is hydrothermally synthesized. • The Bi-CP shows good photoelectric and photocatalytic properties. • Bi-CP shows higher activity than the commercial Bi{sub 2}O{sub 3} for RhB degradation.« less

Cd (II) and holodirected lead (II) 3D-supramolecular coordination polymers based on nicotinic acid: Structure, fluorescence property and photocatalytic activity

NASA Astrophysics Data System (ADS)

Etaiw, Safaa El-din H.; Abd El-Aziz, Dina M.; Marie, Hassan; Ali, Elham

2018-05-01

Two new supramolecular coordination polymers namely {[Cd(NA)2(H2O)]}, SCP 1 and {[Pb(NA)2]}, SCP 2, (NA = nicotinate ligand) were synthesized by self-assembly method and structurally characterized by different analytical and spectroscopic methods. Single-crystal X-ray diffraction showed that SCP 1 extend in three dimensions containing bore structure where the 3D- network is constructed via interweaving zigzag chains. The Cd atom coordinates to (O4N2) atoms forming distorted-octahedral configuration. The structure of SCP 2 extend down the projection of the b-axis creating parallel zigzag 1D-chains connected by μ2-O2 atoms and H-bonds forming a holodirected lead (II) hexagonal bi-pyramid configuration. SCP 2 extend to 3D-network via coordinate and hydrogen bonds. The thermal stability, photoluminescence properties, photocatalytic activity for the degradation of methylene blue dye (MB) under UV-irradiation and sunlight irradiation were also studied.

Syntheses and structural characterization of Co(II) and Cd(II) coordination polymers with 1,4-bis(imidazolyl)butane ligand

NASA Astrophysics Data System (ADS)

Lalegani, Arash; Khalaj, Mehdi; Sedaghat, Sajjad; Łyczko, Krzysztof; Lipkowski, Janusz

2017-11-01

Two new coordination polymers, {[Co(bib)3](PF6)2}n (1) and [Cd (bib) Cl2]n (2), were prepared at room temperature by the reaction of appropriate salts of cobalt (II) and cadmium (II) with the flexible linker ligands 1,4-bis(imidazolyl) butane (bib). The compounds were characterized by elemental analyses, IR spectroscopy and single crystal X-ray diffraction. In the polymeric structure of 1, the Co(II) ion lies on an inversion centre and adopts the CoN6 octahedral geometry, while in the structure of 2, the Cd(II) ions adopt the CdN2Cl4 pseudo-octahedral geometry. In compound 1, six bib ligands are coordinated to one central cobalt (II) to form an open 3D 2-fold interpenetrating framework of the α-polonium (pcu) type topology, while in compound 2 two bib ligands are coordinated to one central cadmium (II) to form 2D network structure.

A self-healing PDMS polymer with solvatochromic properties.

PubMed

Jia, Xiao-Yong; Mei, Jin-Feng; Lai, Jian-Cheng; Li, Cheng-Hui; You, Xiao-Zeng

2015-05-28

Coordination bonds are effective for constructing functional self-healing materials due to their tunable bond strength and metal-ion-induced functionalities. In this work, we incorporate a cobalt(II) triazole complex into a polydimethylsiloxane (PDMS) matrix. The resulting polymers show solvatochromic behaviour as well as self-healing properties.

Heterobimetallic thiocyanato-bridged coordination polymers based on [Hg(SCN){sub 4}]{sup 2-}: Synthesis, crystal structure, magnetic properties and ESR studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jian Fangfang; Xiao Hailian; Liu Faqian

2006-12-15

Three new M/Hg bimetallic thiocyanato-bridged coordination polymers; [Hg(SCN){sub 4}Ni(Im){sub 3}] {sub {infinity}} 1, [Hg(SCN){sub 4}Mn(Im){sub 2}] {sub {infinity}} 2, and [Hg(SCN){sub 4}Cu(Me-Im){sub 2} Hg(SCN){sub 4}Cu(Me-Im){sub 4}] {sub {infinity}} 3, (Im=imidazole, Me-Im=N-methyl-imidazole), have been synthesized and characterized by means of elemental analysis, ESR, and single-crystal X-ray. X-ray diffraction analysis reveals that these three complexes all form 3D network structure, and their structures all contain a thiocyanato-bridged Hg...Hg chain (M=Mn, Ni, Cu) in which the metal and mercury centers exhibit different coordination environments. In complex 1, the [Hg(SCN){sub 4}]{sup 2-} anion connects three [Ni(Im){sub 3}]{sup 2+} using three SCN ligands giving risemore » to a 3D structure, and in complex 2, four SCN ligands bridge [Hg(SCN){sub 4}]{sup 2-} and [Mn(Im){sub 2}]{sup 2+} to form a 3D structure. The structure of 3 contains two copper atoms with distinct coordination environment; one is coordinated by four N-methyl-imidazole ligands and two axially elongated SCN groups, and another by four SCN groups (two elongated) and two N-methyl-imidazole ligands. The magnetic property of complex 1 has been investigated. The spin state structure in hetermetallic NiHgNi systems of complex 1 is irregular. The ESR spectra results of complex 3 demonstrate Cu{sup 2+} ion lie on octahedral environment. -- Graphical abstract: Three new M/Hg bimetallic thiocyanato-bridged coordination polymers; [Hg(SCN){sub 4}Ni(Im){sub 3}] {sub {infinity}} 1, [Hg(SCN){sub 4}Mn(Im){sub 2}] {sub {infinity}} 2, and [Hg(SCN){sub 4}Cu(Me-Im){sub 2} Hg(SCN){sub 4}Cu(Me-Im){sub 4}] {sub {infinity}} 3, (Im=imidazole, Me-Im=N-methyl-imidazole), have been synthesized and characterized by single-crystal X-ray. All coordination polymers possess 3-D structures, and consist of organic base neutral ligands (imidazole and N-methyl-imidazole) and SCN{sup -1} anions. Their structural difference is maicaused by the role of the organic base and metal ions. The complex 1 shows the irregular spin state structure.« less

Ligand-controlled assembly of Cd(II) coordination polymers based on mixed ligands of naphthalene-dicarboxylate and dipyrido[3,2-d:2',3'-f]quinoxaline: From 0D+1D cocrystal, 2D rectangular network (4,4), to 3D PtS-type architecture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu Guocheng; Chen Yongqiang; Wang Xiuli

Three novel Cd(II) coordination polymers, namely, [Cd(Dpq)(1,8-NDC)(H{sub 2}O){sub 2}][Cd(Dpq)(1,8-NDC)].2H{sub 2}O (1), [Cd(Dpq)(1,4-NDC)(H{sub 2}O)] (2), and [Cd(Dpq)(2,6-NDC)] (3) have been obtained from hydrothermal reactions of cadmium(II) nitrate with the mixed ligands dipyrido [3,2-d:2',3'-f]quinoxaline (Dpq) and three structurally related naphthalene-dicarboxylate ligands [1,8-naphthalene-dicarboxylic acid (1,8-H{sub 2}NDC), 1,4-naphthalene-dicarboxylic acid (1,4-H{sub 2}NDC), and 2,6-naphthalene-dicarboxylic acid (2,6-H{sub 2}NDC)]. Single-crystal X-ray diffraction analysis reveals that the three polymers exhibit novel structures due to different naphthalene-dicarboxylic acid. Compound 1 is a novel cocrystal of left- and right-handed helical chains and binuclear complexes and ultimately packed into a 3D supramolecular structure through hydrogen bonds and {pi}-{pi} stacking interactions. Compoundmore » 2 shows a 2D rectangular network (4,4) bridged by 1,4-NDC with two kinds of coordination modes and ultimately packed into a 3D supramolecular structure through inter-layer {pi}-{pi} stacking interactions. Compound 3 is a new 3D coordination polymer with distorted PtS-type network. In addition, the title compounds exhibit blue/green emission in solid state at room temperature. - Graphical abstract: Three novel Cd(II) compounds have been synthesized under hydrothermal conditions exhibiting a systematic variation of architecture by the employment of three structurally related naphthalene-dicarboxylate ligands.« less

Atomic Origins of the Self-Healing Function in Cement–Polymer Composites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nguyen, Manh-Thuong; Wang, Zheming; Rod, Kenton A.

Motivated by recent advances in self-healing cement and epoxy polymer composites, we present a combined ab initio molecular dynamics and sum frequency generation (SFG) spectroscopy study of a calcium-silicate-hydrate/polymer interface. On stable, low-defect surfaces, the polymer only weakly adheres through coordination and hydrogen bonding interactions and can be easily mobilized towards defected surfaces. Conversely, on fractured surfaces, the polymer strongly anchors through ionic Ca-O bonds resulting from the deprotonation of polymer hydroxyl groups. In addition, polymer S-S groups are turned away from the cement/polymer interface, allowing for the self-healing function within the polymer. The overall elasticity and healing properties ofmore » these composites stem from a flexible hydrogen bonding network that can readily adapt to surface morphology. The theoretical vibrational signals associated with the proposed cement-polymer interfacial chemistry were confirmed experimentally by SFG spectroscopy.« less

Atomic Origins of the Self-Healing Function in Cement-Polymer Composites.

PubMed

Nguyen, Manh-Thuong; Wang, Zheming; Rod, Kenton A; Childers, M Ian; Fernandez, Carlos; Koech, Phillip K; Bennett, Wendy D; Rousseau, Roger; Glezakou, Vassiliki-Alexandra

2018-01-24

Motivated by recent advances in self-healing cement and epoxy polymer composites, we present a combined ab initio molecular dynamics and sum frequency generation (SFG) vibrational spectroscopy study of a calcium-silicate-hydrate/polymer interface. On stable, low-defect surfaces, the polymer only weakly adheres through coordination and hydrogen bonding interactions and can be easily mobilized toward defected surfaces. Conversely, on fractured surfaces, the polymer strongly anchors through ionic Ca-O bonds resulting from the deprotonation of polymer hydroxyl groups. In addition, polymer S-S groups are turned away from the cement-polymer interface, allowing for the self-healing function within the polymer. The overall elasticity and healing properties of these composites stem from a flexible hydrogen bonding network that can readily adapt to surface morphology. The theoretical vibrational signals associated with the proposed cement-polymer interfacial chemistry were confirmed experimentally by SFG vibrational spectroscopy.

Development of N- and P- Types of Semiconducting Polymers

DTIC Science & Technology

2015-03-05

Luyao Lu, Tao Xu, Ju Min Lee, Zhiqiang Luo, Feng He, Hyung Il Park, In Hwan Jung, Sang Ouk Kim, Luping Yu, “The Role of N- Doped Multi-wall Carbon...Luping Yu, Di-Jia Liu, Improving Hydrogen Adsorption Enthalpy Through Coordinatively 23 Unsaturated Cobalt in Porous Polymers, Macromolecular...Sang Ouk Kim, Luping Yu, “The Role of N- Doped Multi-wall Carbon Nanotubes in Achieving Highly Efficient Polymer Bulk Heterojunction Solar Cells

A novel one-dimensional manganese(II) coordination polymer containing both dicyanamide and pyrazinamide ligands: Synthesis, spectroscopic investigations, X-ray studies and evaluation of biological activities

NASA Astrophysics Data System (ADS)

Tabrizi, Leila; Chiniforoshan, Hossein; McArdle, Patrick

2015-03-01

A novel 1D coordination polymer {[Mn(μ1,5-dca)2(PZA)2](PZA)2}n, 1, has been synthesized and characterized by single crystal X-ray crystallography. The coordination mode of dicyanamide (dca) and pyrazinamide (PZA) ligands was inferred by IR spectroscopy. The compound 1 was evaluated for in vitro antimycobacterial and antitumor activities. It demonstrated better in vitro activity against Mycobacterium tuberculosis than pyrazinamide and its MIC value was determined. Complex 1 was also screened for its in vitro antitumor activity towards LM3 and LP07 murine cancer cell lines. In addition, the antibacterial activity of complex 1 has been tested against Gram(+) and Gram(-) bacteria and it has shown promising broad range anti-bacterial activity.

Two-dimensional Zn(II) and one-dimensional Co(II) coordination polymers based on benzene-1,4-dicarboxylate and pyridine ligands.

PubMed

Zhou, Li-Juan; Han, Chang-Bao; Wang, Yu-Ling

2016-02-01

Coordination polymers constructed from metal ions and organic ligands have attracted considerable attention owing to their diverse structural topologies and potential applications. Ligands containing carboxylate groups are among the most extensively studied because of their versatile coordination modes. Reactions of benzene-1,4-dicarboxylic acid (H2BDC) and pyridine (py) with Zn(II) or Co(II) yielded two new coordination polymers, namely, poly[(μ4-benzene-1,4-dicarboxylato-κ(4)O:O':O'':O''')(pyridine-κN)zinc(II)], [Zn(C8H4O2)(C5H5N)]n, (I), and catena-poly[aqua(μ3-benzene-1,4-dicarboxylato-κ(3)O:O':O'')bis(pyridine-κN)cobalt(II)], [Co(C8H4O2)(C5H5N)2(H2O)]n, (II). In compound (I), the Zn(II) cation is five-coordinated by four carboxylate O atoms from four BDC(2-) ligands and one pyridine N atom in a distorted square-pyramidal coordination geometry. Four carboxylate groups bridge two Zn(II) ions to form centrosymmetric paddle-wheel-like Zn2(μ2-COO)4 units, which are linked by the benzene rings of the BDC(2-) ligands to generate a two-dimensional layered structure. The two-dimensional layer is extended into a three-dimensional supramolecular structure with the help of π-π stacking interactions between the aromatic rings. Compound (II) has a one-dimensional double-chain structure based on Co2(μ2-COO)2 units. The Co(II) cations are bridged by BDC(2-) ligands and are octahedrally coordinated by three carboxylate O atoms from three BDC(2-) ligands, one water O atom and two pyridine N atoms. Interchain O-H...O hydrogen-bonding interactions link these chains to form a three-dimensional supramolecular architecture.

Fabrication of multilayered thin films via spin-assembly

DOEpatents

Chiarelli, Peter A.; Robinson, Jeanne M.; Casson, Joanna L.; Johal, Malkiat S.; Wang, Hsing-Lin

2007-02-20

An process of forming multilayer thin film heterostructures is disclosed and includes applying a solution including a first water-soluble polymer from the group of polyanionic species, polycationic species and uncharged polymer species onto a substrate to form a first coating layer on the substrate, drying the first coating layer on the substrate, applying a solution including a second water-soluble polymer from the group of polyanionic species, polycationic species and uncharged polymer species onto the substrate having the first coating layer to form a second coating layer on the first coating layer wherein the second water-soluble polymer is of a different material than the first water-soluble polymer, and drying the second coating layer on the first coating layer so as to form a bilayer structure on the substrate. Optionally, one or more additional applying and drying sequences can be repeated with a water-soluble polymer from the group of polyanionic species, polycationic species and uncharged polymer species, so that a predetermined plurality of layers are built up upon the substrate.

Low-cost Electromagnetic Heating Technology for Polymer Extrusion-based Additive Manufacturing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carter, William G.; Rios, Orlando; Akers, Ronald R.

To improve the flow of materials used in in polymer additive manufacturing, ORNL and Ajax Tocco created an induction system for heating fused deposition modeling (FDM) nozzles used in polymer additive manufacturing. The system is capable of reaching a temperature of 230 C, a typical nozzle temperature for extruding ABS polymers, in 17 seconds. A prototype system was built at ORNL and sent to Ajax Tocco who analyzed the system and created a finalized power supply. The induction system was mounted to a PrintSpace Altair desktop printer and used to create several test parts similar in quality to those createdmore » using a resistive heated nozzle.« less

White Polymer Light-Emitting Diodes Based on Exciplex Electroluminescence from Polymer Blends and a Single Polymer.

PubMed

Liang, Junfei; Zhao, Sen; Jiang, Xiao-Fang; Guo, Ting; Yip, Hin-Lap; Ying, Lei; Huang, Fei; Yang, Wei; Cao, Yong

2016-03-09

In this Article, we designed and synthesized a series of polyfluorene derivatives, which consist of the electron-rich 4,4'-(9-alkyl-carbazole-3,6-diyl)bis(N,N-diphenylaniline) (TPA-Cz) in the side chain and the electron-deficient dibenzothiophene-5,5-dioxide (SO) unit in the main chain. The resulting copolymer PF-T25 that did not comprise the SO unit exhibited blue light-emission with the Commission Internationale de L'Eclairage coordinates of (0.16, 0.10). However, by physically blending PF-T25 with a blue light-emitting SO-based oligomer, a novel low-energy emission correlated to exciplex emerged due to the appropriate energy level alignment of TPA-Cz and the SO-based oligomers, which showed extended exciton lifetime as confirmed by time-resolved photoluminescent spectroscopy. The low-energy emission was also identified in copolymers consisting of SO unit in the main chain, which can effectively compensate for the high-energy emission to produce binary white light-emission. Polymer light-emitting diodes based on the exciplex-type single greenish-white polymer exhibit the peak luminous efficiency of 2.34 cd A(-1) and the maximum brightness of 12 410 cd m(-2), with Commission Internationale de L'Eclairage color coordinates (0.27, 0.39). The device based on such polymer showed much better electroluminescent stability than those based on blending films. These observations indicated that developing a single polymer with the generated exciplex emission can be a novel and effective molecular design strategy toward highly stable and efficient white polymer light-emitting diodes.

Semi-Autonomous Control with Cyber-Pain for Artificial Muscles and Smart Structures

DTIC Science & Technology

2010-09-15

avoid some key failure modes. Our approach has built on our developments in dynamic self-sensing and realistic simulation of DEA electromechanics...local controller) to avoid some key failure modes. Our approach has built on our developments in dynamic self-sensing and realistic simulation of DEA...strains [4]. In its natural state long polymer backbones are entangled with intermittent cross-links tying neighbouring backbones together. The soft

A copper-based layered coordination polymer: synthesis, magnetic properties and electrochemical performance in supercapacitors.

PubMed

Liu, Qi; Liu, Xiuxiu; Shi, Changdong; Zhang, Yanpeng; Feng, Xuejun; Cheng, Mei-Ling; Su, Seng; Gu, Jiande

2015-11-28

A copper-based layered coordination polymer ([Cu(hmt)(tfbdc)(H2O)]; hmt = hexamethylenetetramine, tfbdc = 2,3,5,6-tetrafluoroterephthalate; Cu-LCP) has been synthesized, and it has been structurally and magnetically characterized. The Cu-LCP shows ferromagnetic interactions between the adjacent copper(II) ions. Density functional theory calculations on the special model of Cu-LCP support the occurrence of ferromagnetic interactions. As an electrode material for supercapacitors, Cu-LCP exhibits a high specific capacitance of 1274 F g(-1) at a current density of 1 A g(-1) in 1 M LiOH electrolyte, and the capacitance retention is about 88% after 2000 cycles.

Structural diversification and photocatalytic properties of three Cd(II) coordination polymers decorated with different auxiliary ligands

NASA Astrophysics Data System (ADS)

Yin, Wen-Yu; Zhuang, Guo-Yong; Huang, Zuo-Long; Cheng, Hong-Jian; Zhou, Li; Ma, Man-Hong; Wang, Hao; Tang, Xiao-Yan; Ma, Yun-Sheng; Yuan, Rong-Xin

2016-03-01

Three cadmium coordination polymers, [Cd(bismip)]n (1), {[Cd(bismip)(phen)]·H2O}n (2) and {[Cd2(bismip)2(4,4‧-bipy)]·2H2O}n (3) (H2bismip=5-(1H-benzoimidazol-2-ylsulfanylmethyl)-isophthalic acid, phen=1,10-phenanthroline, 4,4‧-bipy=4,4‧-bipyridine) have been prepared under solvothermal conditions. In 1, the [Cd4(bismip)3] units are jointed by bismip ligands to afford a three-dimensional (3D) architecture. Complex 2 exhibits a 3D supramolecular framework based on the interconnection of 1D chains through hydrogen bonding interactions and π-π packing interactions. 3 is a two-fold interpenetrating 3D architecture with a (4·82)(42·84) Schläfli symbol in which 2D layers are interlinked by 4,4‧-bipy ligands. The diverse structures of compounds 1-3 indicate that the auxiliary ligands have significant effects on the final structures. The photoluminescent properties and photocatalytic properties of these coordination polymers in the solid state were also investigated. Remarkably, 3 shows the wide gap semiconductor nature and exhibit excellent photocatalytic performance.

Rethinking Sensitized Luminescence in Lanthanide Coordination Polymers and MOFs: Band Sensitization and Water Enhanced Eu Luminescence in [Ln(C15H9O5)3(H2O)3]n (Ln = Eu, Tb).

PubMed

Einkauf, Jeffrey D; Kelley, Tanya T; Chan, Benny C; de Lill, Daniel T

2016-08-15

A coordination polymer [Ln(C15H9O9)3(H2O)3]n (1-Ln = Eu(III), Tb(III)) assembled from benzophenonedicarboxylate was synthesized and characterized. The organic component is shown to sensitize lanthanide-based emission in both compounds, with quantum yields of 36% (Eu) and 6% (Tb). Luminescence of lanthanide coordination polymers is currently described from a molecular approach. This methodology fails to explain the luminescence of this system. It was found that the band structure of the organic component rather than the molecular triplet state was able to explain the observed luminescence. Deuterated (Ln(C15H9O9)3(D2O)3) and dehydrated (Ln(C15H9O9)3) analogues were also studied. When bound H2O was replaced by D2O, lifetime and emission increased as expected. Upon dehydration, lifetimes increased again, but emission of 1-Eu unexpectedly decreased. This reduction is reasoned through an unprecedented enhancement effect of the compound's luminescence by the OH/OD oscillators in the organic-to-Eu(III) energy transfer process.

Graphene oxide coated coordination polymer nanobelt composite material: a new type of visible light active and highly efficient photocatalyst for Cr(VI) reduction.

PubMed

Shi, Gui-Mei; Zhang, Bin; Xu, Xin-Xin; Fu, Yan-Hong

2015-06-28

A visible light active photocatalyst was synthesized successfully by coating graphene oxide (GO) on a coordination polymer nanobelt (CPNB) using a simple colloidal blending process. Compared with neat CPNB, the resulting graphene oxide coated coordination polymer nanobelt composite material (GO/CPNB) exhibits excellent photocatalytic efficiency in the reduction of K2Cr2O7 under visible light irradiation. In the composite material, GO performs two functions. Firstly, it cuts down the band gap (E(g)) of the photocatalyst and extends its photoresponse region from the ultraviolet to visible light region. Secondly, GO exhibits excellent electron transportation ability that impedes its recombination with holes, and this can enhance photocatalytic efficiency. For GO, on its surface, the number of functional groups has a great influence on the photocatalytic performance of the resulting GO/CPNB composite material and an ideal GO"coater" to obtain a highly efficient GO/CPNB photocatalyst has been obtained. As a photocatalyst that may be used in the treatment of Cr(VI) in wastewater, GO/CPNB exhibited outstanding stability during the reduction of this pollutant.

Synthesis, crystal structures and luminescent properties of two 4 d-4 f Ln-Ag heterometallic coordination polymers based on anion template

NASA Astrophysics Data System (ADS)

Fan, Le-Qing; Chen, Yuan; Wu, Ji-Huai; Huang, Yun-Fang

2011-04-01

Two new 4 d-4 f Ln-Ag heterometallic coordination polymers, {[ Ln3Ag 5(IN) 10(H 2O) 7]·4(ClO 4)·4(H 2O)} n ( Ln=Eu ( 1) and Sm ( 2), HIN=isonicotinic acid), have been synthesized under hydrothermal conditions by reactions of Ln2O 3, AgNO 3, HIN and HClO 4, and characterized by elemental analysis, IR, thermal analysis and single-crystal X-ray diffraction. It is proved that HClO 4 not only adjusts the pH value of the reaction mixture, but also acts as anion template. The structure determination reveals that 1 and 2 are isostructural and feature a novel two-dimensional (2D) layered hetrometallic structure constructed from one-dimensional Ln-carboxylate chains and pillared Ag(IN) 2 units. The 2D layers are further interlinked through Ag⋯Ag and Ag⋯O(ClO 4-) multiple weak interactions, which form a rare Ag-ClO 4 ribbon in lanthanide-transition metal coordination polymers, to give rise to a three-dimensional supramolecular architecture. Moreover, the luminescent properties of these two compounds have also been investigated at room temperature.

Luminescent Thermochromism of 2D Coordination Polymers Based on Copper(I) Halides with 4-Hydroxythiophenol

PubMed Central

Troyano, Javier; Perles, Josefina; Amo-Ochoa, Pilar; Martínez, Jose Ignacio; Concepción Gimeno, Maria; Fernández-Moreira, Vanesa; Zamora, Félix; Delgado, Salomé

2016-01-01

Solvothermal reactions between copper(I) halides and 4-mercaptophenol give rise to the formation of three coordination polymers with general formula [Cu3X(HT)2]n (X= Cl, 1; Br, 2; and I, 3). The structures of these coordination polymers have been determined by X-ray diffraction at both room temperature and low temperature (110 K), showing a general shortening in Cu-S, Cu-X and Cu···Cu bond distances at low temperatures. 1 and 2 are isostructural consisting of layers in which the halogen ligands act as μ3-bridges joining two Cu1 and one Cu2 atoms whereas in 3 the iodine ligands is as μ4-mode but the layers are quasi-isostructural with 1 or 2. These compounds show a reversible thermochromic luminescence, with strong orange emission for 1 and 2, but weaker for 3 at room temperature, while upon cooling at 77 K 1 and 2 show stronger yellow as well as 3 displays stronger green emission. DFT calculations have been used to rationalise these observations. These results suggest a high potential for this novel and promising stimuli-responsive materials. PMID:27809369

Luminescent Thermochromism of 2D Coordination Polymers Based on Copper(I) Halides with 4-Hydroxythiophenol.

PubMed

Troyano, Javier; Perles, Josefina; Amo-Ochoa, Pilar; Martínez, Jose Ignacio; Concepción Gimeno, Maria; Fernández-Moreira, Vanesa; Zamora, Félix; Delgado, Salomé

2016-12-12

Solvothermal reactions between copper(I) halides and 4-mercaptophenol give rise to the formation of three coordination polymers with general formula [Cu 3 X(HT) 2 ] n (X=Cl, 1; Br, 2; and I, 3). The structures of these coordination polymers have been determined by X-ray diffraction at both room- and low temperature (110 K), showing a general shortening in Cu-S, Cu-X and Cu-Cu bond lengths at low temperatures. 1 and 2 are isostructural, consisting of layers in which the halogen ligands act as μ 3 -bridges joining two Cu1 and one Cu2 atoms whereas in 3 the iodine ligands is as μ 4 -mode but the layers are quasi-isostructural with 1 or 2. These compounds show a reversible thermochromic luminescence, with strong orange emission for 1 and 2, but weaker for 3 at room temperature, whereas upon cooling at 77 K 1 and 2 show stronger yellow emission, and 3 displays stronger green emission. DFT calculations have been used to rationalize these observations. These results suggest a high potential for this novel and promising stimuli-responsive materials. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bismuth-, Tin-, and Lead-Containing Metal-Organic Materials: Synthesis, Structure, Photoluminescence, Second Harmonic Generation, and Ferroelectric Properties

NASA Astrophysics Data System (ADS)

Wibowo, Arief Cahyo

Metal-Organic Materials (MOMs) contain metal moieties and organic ligands that combine to form discrete (e.g. metal-organic polyhedra, spheres or nanoballs, metal-organic polygons) or polymeric structures with one-, two-, or three-dimensional periodicities that can exhibit a variety of properties resulting from the presence of the metal moieties and/or ligand connectors in the structure. To date, MOMs with a range of functional attributes have been prepared, including record-breaking porosity, catalytic properties, molecular magnetism, chemical separations and sensing ability, luminescence and NLO properties, multiferroic, ferroelectric, and switchable molecular dielectric properties. We are interested in synthesizing non-centrosymmetric MOM single crystals possessing one of the ten polar space groups required for non-linear optical properties (such as second harmonic generation) and ferroelectric applications. This thesis is divided into two main parts: materials with optical properties, such as photoluminescence and materials for targeted applications such as second harmonic generation and ferroelectric properties. This thesis starts with an introduction describing material having centrosymmetric, non-polar space groups, single crystals structures and their photoluminescence properties. These crystals exhibit very interesting and rare structures as well as interesting photoluminescence properties. Chapters 2-5 of this thesis focus on photoluminescent properties of new MOMs, and detail the exploratory research involving the comparatively rare bismuth, lead, and tin coordination polymers. Specifically, the formation of single white-light emitting phosphors based on the combination of bismuth or lead with pyridine-2,5-dicarboxylate is discussed (Chapter 2). The observation of a new Bi2O2 layer and a new Bi4O 3 chain in bismuth terephthalate-based coordination polymers is presented in Chapter 3, while the formation of diverse structures of tin-based coordination polymer ranging from 1D supramolecular structures to true 3D coordination polymers is covered in Chapter 4. The observation of a new 2D Kagome lattice and unique layered perovskite-type bismuth-based coordination polymers and their photoluminescence properties is the focus of Chapter 5. In chapters 6 and 7, a successful approach to implement our novel hybrid strategy for synthesizing enantiomerically pure single crystals consisting of Second Order Jahn Teller (SOJT)-possessing main group metal cations, specifically bismuth and tin, and homochiral ligands or unsymmetric ligands is discussed. The new MOMs with polar space groups exhibit second harmonic generation and have potential for ferroelectric properties.

Quantitative property-structural relation modeling on polymeric dielectric materials

NASA Astrophysics Data System (ADS)

Wu, Ke

Nowadays, polymeric materials have attracted more and more attention in dielectric applications. But searching for a material with desired properties is still largely based on trial and error. To facilitate the development of new polymeric materials, heuristic models built using the Quantitative Structure Property Relationships (QSPR) techniques can provide reliable "working solutions". In this thesis, the application of QSPR on polymeric materials is studied from two angles: descriptors and algorithms. A novel set of descriptors, called infinite chain descriptors (ICD), are developed to encode the chemical features of pure polymers. ICD is designed to eliminate the uncertainty of polymer conformations and inconsistency of molecular representation of polymers. Models for the dielectric constant, band gap, dielectric loss tangent and glass transition temperatures of organic polymers are built with high prediction accuracy. Two new algorithms, the physics-enlightened learning method (PELM) and multi-mechanism detection, are designed to deal with two typical challenges in material QSPR. PELM is a meta-algorithm that utilizes the classic physical theory as guidance to construct the candidate learning function. It shows better out-of-domain prediction accuracy compared to the classic machine learning algorithm (support vector machine). Multi-mechanism detection is built based on a cluster-weighted mixing model similar to a Gaussian mixture model. The idea is to separate the data into subsets where each subset can be modeled by a much simpler model. The case study on glass transition temperature shows that this method can provide better overall prediction accuracy even though less data is available for each subset model. In addition, the techniques developed in this work are also applied to polymer nanocomposites (PNC). PNC are new materials with outstanding dielectric properties. As a key factor in determining the dispersion state of nanoparticles in the polymer matrix, the surface tension components of polymers are modeled using ICD. Compared to the 3D surface descriptors used in a previous study, the model with ICD has a much improved prediction accuracy and stability particularly for the polar component. In predicting the enhancement effect of grafting functional groups on the breakdown strength of PNC, a simple local charge transfer model is proposed where the electron affinity (EA) and ionization energy (IE) determines the main charge trap depth in the system. This physical model is supported by first principle computation. QSPR models for EA and IE are also built, decreasing the computation time of EA and IE for a single molecule from several hours to less than one second. Furthermore, the designs of two web-based tools are introduced. The tools represent two commonly used applications for QSPR studies: data inquiry and prediction. Making models and data public available and easy to use is particularly crucial for QSPR research. The web tools described in this work should provide a good guidance and starting point for the further development of information tools enabling more efficient cooperation between computational and experimental communities.

A molecular design principle of lyotropic liquid-crystalline conjugated polymers with directed alignment capability for plastic electronics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Bong-Gi; Jeong, Eun Jeong; Chung, Jong Won

Conjugated polymers with a one-dimensional p-orbital overlap exhibit optoelectronic anisotropy. Their unique anisotropic properties can be fully realized in device applications only when the conjugated chains are aligned. Here, we report a molecular design principle of conjugated polymers to achieve concentration-regulated chain planarization, self-assembly, liquid-crystal-like good mobility and non-interdigitated side chains. As a consequence of these intra- and intermolecular attributes, chain alignment along an applied flow field occurs. This liquid-crystalline conjugated polymer was realized by incorporating intramolecular sulphur–fluorine interactions and bulky side chains linked to a tetrahedral carbon having a large form factor. By optimizing the polymer concentration and themore » flow field, we could achieve a high dichroic ratio of 16.67 in emission from conducting conjugated polymer films. Two-dimensional grazing-incidence X-ray diffraction was performed to analyse a well-defined conjugated polymer alignment. Thin-film transistors built on highly aligned conjugated polymer films showed more than three orders of magnitude faster carrier mobility along the conjugated polymer alignment direction than the perpendicular direction.« less

A triple helical calcium-based coordination polymer with strong blue fluorescent emission

NASA Astrophysics Data System (ADS)

Yu, Liang-Cai; Chen, Zhen-Feng; Liang, Hong; Zhou, Chun-Shan; Li, Yan

2005-08-01

A hydrothermal reaction of 1,3-dicyanobenzene and Ca(OH)2 yielded a triple helical calcium-based coordination polymer of the formula, C20H25Ca2.50O18.50 (1). The 1,3-benzenecarboxylate anion, found in the final product was generated in situ during the synthesis by the hydrolysis of 1,3-dicyanobenzene. X-ray diffraction study shows that the complex 1 crystallizes in the monoclinic system, C2/c space group, a=15.5701(5), b=21.4445(7), c=17.1601(6) Å, β=111.7400(7)°, V=5322.1(3) Å3, Z=8, Dc=1.651 Mg/m3. The calcium atoms show differences in the coordination environments. Complex 1 emits strong blue fluorescent light (λem(max)=419 nm) when it is excited by UV light (λex(max)=316 nm) in the solid state at room temperature.

Tuning zinc coordination architectures by benzenedicarboxylate position isomers and bis(triazole)

NASA Astrophysics Data System (ADS)

Peng, Yan-fen; Li, Ke; Zhao, Shan; Han, Shan-shan; Li, Bao-long; Li, Hai-Yan

2015-08-01

Three position isomers 1,2-, 1,3-, 1,4-benzenedicarboxylate and 1,4-bis(1,2,4-triazol-4-yl)benzene were used to assembly zinc(II) coordination polymers {[Zn2(btx)0.5(1,2-bdc)2(H2O)]·H2O}n (1), {[Zn(btx)(1,3-bdc)]·2H2O·(DMF)}n (2) and {[Zn(btx)(1,4-bdc)]·3H2O}n (3). 1 is a (3,4,4,4)-connected two-dimensional network with point symbol (42·6)(44·62)(43·62·8)(42·6·103). 2 shows a two-dimensional (4,4) network. 3 exhibits a 5-fold interpenetrated three-dimensional diamondoid network. The structural versatility shows that the structures of coordination polymers can be tuned by the position isomers ligands. The luminescence and thermal stability were investigated.

A new series of lanthanide coordination polymers with 2,2‧-bipyridine and glutaric acid: Synthesis, crystal structures and properties of [Ln(bipy)(glut)(NO3)

NASA Astrophysics Data System (ADS)

Wang, Chunguang; Xing, Yongheng; Li, Zhangpeng; Li, Jing; Zeng, Xiaoqing; Ge, Maofa; Niu, Shuyun

2009-08-01

A series of new lanthanide coordination polymers, with the formula [Ln(bipy)(glut)(NO 3)] (Ln = Eu ( 1), Tb ( 2), Sm ( 3), Pr ( 4); bipy = 2,2'-bipyridine; H 2glut = glutaric acid), have been synthesized under the hydrothermal condition and characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction, and single-crystal X-ray diffraction. Structural analyses reveal that all four complexes are isostructural and crystallized in monoclinic system, P2 1/ c space group. For these complexes, the Ln 3+ are all linked through glutaric acid ligands to form 1D chain-like polymeric structures, and bipy and NO3- are coordinated on two sides of the chains. The thermogravimetric analysis of 1 and photoluminescent properties of 1 and 2 are discussed in detail.

Controlled placement and orientation of nanostructures

DOEpatents

Zettl, Alex K; Yuzvinsky, Thomas D; Fennimore, Adam M

2014-04-08

A method for controlled deposition and orientation of molecular sized nanoelectromechanical systems (NEMS) on substrates is disclosed. The method comprised: forming a thin layer of polymer coating on a substrate; exposing a selected portion of the thin layer of polymer to alter a selected portion of the thin layer of polymer; forming a suspension of nanostructures in a solvent, wherein the solvent suspends the nanostructures and activates the nanostructures in the solvent for deposition; and flowing a suspension of nanostructures across the layer of polymer in a flow direction; thereby: depositing a nanostructure in the suspension of nanostructures only to the selected portion of the thin layer of polymer coating on the substrate to form a deposited nanostructure oriented in the flow direction. By selectively employing portions of the method above, complex NEMS may be built of simpler NEMSs components.

A series of Zn/Cd coordination polymers constructed from 1,4-naphthalenedicarboxylate and N-donor ligands: Syntheses, structures and luminescence sensing of Cr{sup 3+} in aqueous solutions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Dong-Cheng; Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, Shantou 515063; Fan, Yan

A novel series of Zn/Cd coordination polymers based on H{sub 3}L, namely, [Zn{sub 2}(HL){sub 2}(bipy){sub 2}(H{sub 2}O){sub 6}]{sub n} (1), [Zn(HL)(phen)]{sub n} (2), [Cd{sub 3}L{sub 2}(bbi){sub 3}]{sub n} (3), [Zn{sub 3}L{sub 2}(bbi){sub 3}]{sub n} (4) [(H{sub 3}L =4-[(1-carboxynaphthalen-2-yl)oxy]phthalic acid, bipy =4,4′-bipyridine, phen =1,10-phenanthroline, bbi =1,1′-(1,4-butanediyl)bis(imidazole] have been successfully synthesized by solvothermal reaction. Compound 1 possesses two diverse 1D chains constructed by different bipy coligands, which were further connected to form a 3D supramolecular architecture by hydrogen bonding interactions. Compound 2 possesses a complicated 1D chain based on secondary building unit (SBU) with binuclear Zn cluster. Compounds 3 and 4 exhibitmore » similar 2D→3D framework, which can be rationalized as (3,4,4)-connected 3D net with a Schläfli symbol of (6{sup 3}.8.10{sup 2}){sub 2}(6{sup 3}){sub 2}(6{sup 4}.8.10). In particular, compound 3 exhibited a high sensitivity for Cr{sup 3+} in aqueous solutions, which suggest that compound 3 is a promising luminescent probe for selectively sensing Cr{sup 3+}. - Graphical abstract: A series of novel Zn/Cd coordination polymers have been successfully synthesized by solvothermal reaction. The unique 3D Cd{sup 2+} polymer containing bbi as second ligand demonstrates high sensitivity for detection of toxic Cr{sup 3+} in aqueous solutions. Display Omitted - Highlights: • π-conjugated semirigid tricarboxylate ligands with naphthalene rings(H{sub 3}L) were rationally designed. • Four Zn/Cd coordination polymers based on H{sub 3}L have been successfully synthesized by solvothermal reaction. • Compound 3 is a promising luminescent probe for selectively sensing Cr{sup 3+} with high sensitivity in aqueous solutions.« less

Coordination Polymer of M(II)-Pyrazinamide (M = Co, Cd) with Double End-to-End Thiocyanate Bridge

NASA Astrophysics Data System (ADS)

Ponco Prananto, Yuniar

2018-01-01

Pyrazinamide (pza, C4N2H3-CONH2) is a good ligand for coordination polymer. Their transition metal complexes are known to have antibacterial activities, magnetic properties, etc. Coordination polymers of M(II)-pyrazinamide with thiocyanate (M = Co (a), Cd (b)), prepared using bench-top layering technique with M(II):pza:SCN ratio of 1:2:2, is successfully crystallised at room temperature. Single crystal XRD was used to determine the crystal structure. Infrared and melting point determination were also performed. Crystal structure of both complexes, solved in Triclinic P-1, show that each octahedral metal centre is connected to two adjacent metal centres by double end-to-end thiocyanate bridge forming a 1D polymeric structure with M···M distances of 5.524 Å (in a) and 5.887 Å (in b). Two monodentate pyrazinamide ligands occupy the rest of the coordination sites on the metal centre in a trans relationship. Only in complex a, one lattice pyrazinamide molecule is involved in the asymmetric unit. Crystal packing of both a and b are also displaying non-covalent networks as a result of hydrogen-bonding involving the pyrazine ring, amide and carbonyl groups between adjacent chains and π···π interactions (only occurred in a). In addition, the observed melting points of both a and b are relatively close to each other (around 180°C), and ATR-IR spectra support the presence of the bridging thiocyanate and terminal pyrazinamide.

Utilization of mixed ligands to construct diverse Ni(II)-coordination polymers based on terphenyl-2,2‧,4,4‧-tetracarboxylic acid and varied N-donor co-ligands

NASA Astrophysics Data System (ADS)

Wang, Chao; Zhao, Jun; Xia, Liang; Wu, Xue-Qian; Wang, Jian-Fang; Dong, Wen-Wen; Wu, Ya-Pan

2016-06-01

Three new coordination polymers, namely, {[Ni(H2L)(bix)(H2O)2]·2h2O}n (1), {[Ni(HL)(Hdpa)(H2O)2]·H2O}n (2), {[Ni(L)0.5(bpp)(H2O)]·H2O}n (3) (H4L=terphenyl-2,2‧,4,4‧-tetracarboxylic acid; bix=1,4-bis(imidazol-1-ylmethyl)benzene; dpa =4,4‧-dipyridylamine; bpp=1,3-bis(4-pyridyl)propane), based on rigid H4L ligand and different N-donor co-ligands, have been synthesized under hydrothermal conditions. Compound 1 features a 3D 4-connected 66-dia-type framework with H4L ligand adopts a μ2-bridging mode with two symmetry-related carboxylate groups in μ1-η1:η0 monodentate mode. Compound 2 displays a 1D [Ni(HL)(Hdpa)]n ribbon chains motif, in which the H4L ligand adopts a μ2-bridging mode with two carboxylate groups in μ1-η1:η1 and μ1-η1:η0 monodentate modes, while 3 possesses a (4,4)-connected 3D frameworks with bbf topology, with H4L ligand displays a μ4-bridging coordination mode. The H4L ligand displays not only different deprotonated forms but also diverse coordination modes and conformations. The structural diversities among 1-3 have been carefully discussed, and the roles of N-donor co-ligands in the self-assembly of coordination polymers have been well documented.

Synthesis, crystal structure, and magnetic properties of two-dimensional divalent metal glutarate/dipyridylamine coordination polymers, with a single crystal-to-single crystal transformation in the copper derivative

DOE Office of Scientific and Technical Information (OSTI.GOV)

Montney, Matthew R.; Supkowski, Ronald M.; Staples, Richard J.

Hydrothermal reaction of divalent metal chlorides with glutaric acid and 4,4'-dipyridylamine (dpa) has afforded an isostructural family of coordination polymers with formulation [M(glu)(dpa)]{sub n} (M=Co (1), Ni (2), Cu (3); glu=glutarate). Square pyramidal coordination is seen in 1-3, with semi-ligation of a sixth donor to produce a '5+1' extended coordination sphere. Neighboring metal atoms are linked into 1D [M(glu)]{sub n} neutral chains through chelating/monodentate bridging glutarate moieties with a syn-anti binding mode, and semi-chelation of the pendant carboxylate oxygen. These chains further connect into 2D layers through dipodal dpa ligands. Neighboring layers stack into the pseudo 3D crystal structure ofmore » 1-3 through supramolecular hydrogen bonding between dpa amine units and the semi-chelated glutarate oxygen atoms. The variable temperature magnetic behavior of 1-3 was explored and modeled as infinite 1D Heisenberg chains. Notably, complex 3 undergoes a thermally induced single crystal-to-single crystal transformation between centric and acentric space groups, with a conformationally disordered unilayer structure at 293 K and an ordered bilayer structure at 173 K. All materials were further characterized via infrared spectroscopy and elemental and thermogravimetric analyses. - Graphical abstract: The coordination polymers [M(glu)(dpa)]{sub n} (M=Co (1), Ni (2), Cu (3); glu=glutarate, dpa=4,4'-dipyridylamine) exhibit 2D layer structures based on 1D [M(glu)]{sub n} chains linked through dpa tethers. Antiferromagnetic coupling is observed for 2 and 3, while ferromagnetism is predominant in 1. Compound 3 undergoes a thermally induced single crystal-to-single crystal transformation from an acentric to a centrosymmetric space group.« less

Hydrothermal recrystallization of transition metal nitroprussides. Formation of the most stable phases

NASA Astrophysics Data System (ADS)

Echevarría, F.; Reguera, L.; González M, M.; Galicia, J.; Ávila, M.; Reguera, E.

2018-02-01

Hydrothermal recrystallization appears to be an appropriate treatment to explore the structural diversity of porous coordination polymers. In this contribution, such a post-synthesis treatment is applied to divalent transition metal nitroprussides, T[Fe(CN)5NO]•xH2O with T =Mn, Fe, Co, Ni, Cu, Zn, Cd. This family of compounds forms an interesting series of nanoporous coordination polymers with a wide structural diversity, related to the synthesis route used and the solid hydration degree (x). The effect of a hydrothermal recrystallization of previously prepared fine powders using the precipitation method, on their crystal structure and related properties is herein discussed. In this series of coordination polymers, for Fe, Co, Ni the precipitated powders are obtained as cubic phase, with a high porosity related to presence of systematic vacancies for building unit [Fe(CN)5NO]. For Fe and Co a structural transition, from cubic to orthorhombic, was observed, which is associated to formation of a most compact structure. The crystal structure for the new orthorhombic phases was refined from the collected powder HR-XRD patterns. For Ni, the cubic phase remains stable even for large heating time, which is ascribed to the high polarizing power of this metal. The high porosity for the cubic phase allows an easy accommodation for the local deformations around the Ni atom coordination sphere. The structural information from XRD was complemented with CO2 and H2 adsorption and TG data, IR and UV-vis spectra, and magnetic measurements. The magnetic data, through the presence of spin-orbit coupling for Fe and Co in the two phases, provide fine details on the coordination environment for the metal linked at the N ends of the CN group.

Novel octanuclear copper(I) metallomacrocycles and their transformation into hexanuclear 2-dimensional grids of copper(i) coordination polymers containing cyclodiphosphazanes, [(micro-NtBuP)2(NC4H8X)2] (X = NMe, O).

PubMed

Suresh, D; Balakrishna, Maravanji S; Mague, Joel T

2008-07-07

Novel octanuclear copper(I) macrocyclic complexes and hexanuclear 2-dimensional grid-like polymers containing [P(micro-NR)](2) scaffold in which the anionic moieties are trapped inside the cationic macrocyclic cavities are reported.

Synthesis, structures and fluorescent properties of two novel lanthanide [Ln = Ce(III), Pr(III)] coordination polymers based on 1,3-benzenedicarboxylate and 2-(4-methoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline ligands

NASA Astrophysics Data System (ADS)

Wang, Lei; Ni, Liang; yao, Jia

2012-09-01

Two structurally diverse coordination polymers [Ce2(m-BDC)2(m-HBDC)2(MOPIP)2·3/2H2O]n (1) and [Pr2(m-BDC)3(MOPIP)2·H2O]n(2) have been synthesized by hydrothermal reaction of lanthanide chloride with mixed ligands benzene-1,3-dicarboxylic acid and 2-(4-methoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (MOPIP). The crystal structures of the complexes are zipper-like chains of octacoordinate Ln3+ ions, in which Ln3+ ions are bridged in different coordination modes by m-BDC2+ and decorated by MOPIP ligands. These chains are further assembled into three-dimensional supramolecular framework by π⋯π stacking and hydrogen bonding interactions. The fluorescent property and thermal stability were also investigated. Additionally, Natural bond orbital (NBO) analysis of complex 2 shows a weak covalent interaction between the coordinated atoms and Pr3+ ions.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Chao; Zhao, Jun, E-mail: junzhao08@126.com; State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 35002

Three new coordination polymers, namely, {[Ni(H_2L)(bix)(H_2O)_2]·2h_2O}{sub n} (1), {[Ni(HL)(Hdpa)(H_2O)_2]·H_2O}{sub n} (2), {[Ni(L)_0_._5(bpp)(H_2O)]·H_2O}{sub n} (3) (H{sub 4}L=terphenyl-2,2′,4,4′-tetracarboxylic acid; bix=1,4-bis(imidazol-1-ylmethyl)benzene; dpa =4,4′-dipyridylamine; bpp=1,3-bis(4-pyridyl)propane), based on rigid H{sub 4}L ligand and different N-donor co-ligands, have been synthesized under hydrothermal conditions. Compound 1 features a 3D 4-connected 6{sup 6}-dia-type framework with H{sub 4}L ligand adopts a μ{sub 2}-bridging mode with two symmetry-related carboxylate groups in μ{sub 1}-η{sup 1}:η{sup 0} monodentate mode. Compound 2 displays a 1D [Ni(HL)(Hdpa)]{sub n} ribbon chains motif, in which the H{sub 4}L ligand adopts a μ{sub 2}-bridging mode with two carboxylate groups in μ{sub 1}-η{sup 1}:η{sup 1} and μ{sub 1}-η{supmore » 1}:η{sup 0} monodentate modes, while 3 possesses a (4,4)-connected 3D frameworks with bbf topology, with H{sub 4}L ligand displays a μ{sub 4}-bridging coordination mode. The H{sub 4}L ligand displays not only different deprotonated forms but also diverse coordination modes and conformations. The structural diversities among 1–3 have been carefully discussed, and the roles of N-donor co-ligands in the self-assembly of coordination polymers have been well documented. - Graphical abstract: Three nickel coordination polymers with different architectures based on mixed ligand system were synthesized and structurally characterized. Topology analyses indicate that 1 shows the 4-connected 6{sup 6}-dia net, 1D ribbon chains for 2 and 3D (4,4)-connected bbf network for 3. Display Omitted - Highlights: • Three Ni-based coordination polymers with distinct features have been prepared. • Compound 1 features a 3D 4-connected 66-dia-type framework, 2 displays a 1D [Ni(HL)(Hdpa)]{sub n} ribbon chains motif, while 3 possesses a (4,4)-connected 3D frameworks with bbf topology. • The “mixed ligand assembled” strategy is significant potential for network design.« less

Self-assembly of metal-organic supramolecules: from a metallamacrocycle and a metal-organic coordination cage to 1D or 2D coordination polymers based on flexible dicarboxylate ligands.

PubMed

Dai, Fangna; Dou, Jianmin; He, Haiyan; Zhao, Xiaoliang; Sun, Daofeng

2010-05-03

To assemble metal-organic supramolecules such as a metallamacrocycle and metal-organic coordination cage (MOCC), a series of flexible dicarboxylate ligands with the appropriate angle, 2,2'-(2,3,5,6-tetramethyl-1,4-phenylene)bis(methylene)bis(sulfanediyl)dibenzoic acid (H(2)L(1)), 2,2'-(2,5-dimethyl-1,4-phenylene)bis(methylene)bis(sulfanediyl)dibenzoic acid (H(2)L(2)), 2,2'-(2,4,6-trimethyl-1,3-phenylene)bis(methylene)bis(sulfanediyl)dinicotinic acid (H(2)L(3)), and 2,2'-(2,4,6-trimethyl-1,3-phenylene)bis(methylene)bis(sulfanediyl)dibenzoic acid (H(2)L(4)), have been designed and synthesized. Using these flexible ligands to assemble with metal ions, six metal-organic supramolecules, Cd(2)(L(1))(2)(dmf)(4)(H(2)O)(2).H(2)O (1), Mn(3)((1)L(2))(2)((2)L(2))(dmf)(2)(H(2)O)(2).5dmf (2), Cu(4)(L(3))(4)(H(2)O)(4).3dmf (3), Cu(4)(L(4))(4)(dmf)(2)(EtOH)(2).8dmf.6H(2)O (4), Mn(4)(L(4))(4)(dmf)(4)(H(2)O)(4).6dmf.H(2)O (5), and Mn(3)(L(4))(3)(dmf)(4).2dmf.3H(2)O (6), possessing a rectangular macrocycle, MOCCs or their extensions, and 1D or 2D coordination polymers, have been isolated. All complexes have been characterized by single-crystal X-ray diffraction, elemental analysis, and thermogravimetric analysis. Complex 1 is a discrete rectangular macrocycle, while complex 2 is a 2D macrocycle-based coordination polymer in which the L(2) ligand adopts both syn and anti conformations. Complexes 3-5 are discrete MOCCs in which two binuclear metal clusters are engaged by four organic ligands. The different geometries of the secondary building units (SBUs) and the axial coordinated solvates on the SBUs result in their different symmetries. Complex 6 is a 1D coordination polymer, extended from a MOCC made up of two metal ions and three L(4) ligands. All of the flexible dicarboxylate ligands adopt a syn conformation except that in complex 2, indicating that the syn conformational ligand is helpful for the formation of a metallamacrocycle and a MOCC. The magnetic properties of complexes 5 and 6 have also been studied.

Homochiral coordination polymers constructed from aminocarboxylate derivates: Effect of bipyridine on the amidation reaction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen Jianshan; Sheng Tianlu; Hu Shengmin

2012-08-15

Using aminocarboxylate derivates (S)-N-(4-cyanobenzoic)-glutamic acid (denoted as cbg, 1a) and (S)-N-(4-nitrobenzoic)-glutamic acid (denoted as nbg, 1b) as chiral ligands, five new homochiral coordination polymers formulated as [Cu(cbg)(H{sub 2}O){sub 2}]{sub n} (3), [Cu(cbop){sub 2}(4,4 Prime -bipy)(H{sub 2}O)]{sub n} (4) (cbop=(S)-N-(4-cyanobenzoic)-5-oxoproline, 4,4 Prime -bipy=4,4 Prime -bipyridine), {l_brace}[Cu(nbop){sub 2}(4,4 Prime -bipy)]{center_dot}4H{sub 2}O{r_brace}{sub n} (5) (nbop=(S)-N-(4-nitrobenzoic)-5-oxoproline), {l_brace}[Cd(nbop){sub 2}(4,4 Prime -bipy)]{center_dot}2H{sub 2}O{r_brace}{sub n} (6), and [Ni(nbop){sub 2}(4,4 Prime -bipy)(H{sub 2}O){sub 2}]{sub n} (7) have been hydrothermally synthesized and structurally characterized. Single-crystal X-ray diffraction study reveals that the original chirality of aminocarboxylate derivates is maintained in all these complexes. Complexes 3, 4, and 7 are one-dimensionalmore » infinite chain coordination polymers, while complexes 5 and 6 possess two-dimensional network structures. In situ cyclization of 1a and 1b was taken place in the formation of complexes 4-7, which may be due to the competition of 4,4 Prime -bipyridine with chiral ligands during the coordination process. Preliminary optical behavior investigation indicates that ligands 1a, 1b, and complexes 6, 7 are nonlinear optical active. - Graphical abstract: Using aminocarboxylate derivates as chiral ligands, five new homochiral coordination polymers possessing second harmonic generation activities have been hydrothermally synthesized. Highlights: Black-Right-Pointing-Pointer Two new chiral aminocarboxylate derivates were firstly synthesized. Black-Right-Pointing-Pointer Five new homochiral metal organic complexes were obtained hydrothermally based on these ligands. Black-Right-Pointing-Pointer Intramolecular amidation was taken place on the aminocarboxylate derivates during the formation of these complexes. Black-Right-Pointing-Pointer In situ amidation may be due to the impact of 4,4 Prime -bipyridine. Black-Right-Pointing-Pointer The homochiral complexes are nonlinear optical active.« less

Syntheses, structures, electrochemistry and catalytic oxidation degradation of organic dyes of two new coordination polymers derived from Cu(II) and Mn(II) and 1-(tetrazo-5-yl)-4-(triazo-1-yl)benzene

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Ming; Mu, Bao; Huang, Ru-Dan, E-mail: huangrd@bit.edu.cn

Two new coordination polymers (CPs), namely, [Cu{sub 2}(ttbz)(H{sub 2}btc){sub 2}(OH)]{sub n} (1) and [Mn(ttbz){sub 2}(H{sub 2}O){sub 2}]{sub n} (2) (Httbz =1-(tetrazo-5-yl)-4-(triazo-1-yl)benzene, H{sub 3}btc =1,3,5-benzenetricarboxylic acid), have been hydrothermally synthesized and structurally characterized. Complex 1 exhibits a (3,5,5,5)-connected 2D layer with a Schläfli symbol of (3·4{sup 2})(3·4{sup 4}0.5{sup 2}0.6{sup 3})(3{sup 2}0.4{sup 4}0.5{sup 2}0.6{sup 2})(3{sup 2}0.4{sup 4}0.5{sup 3}0.6), in which the ttbz{sup -} ligand can be described as μ{sub 5}-bridge, linking Cu(II) ions into a 2D layer and H{sub 2}btc{sup -} ions play a supporting role in complex 1. The ttbz{sup -} ligand in complex 2 represents the bridging coordination mode, connectingmore » two Mn(II) ions to form the infinite 1D zigzag chains, respectively, which are further connected by two different types of hydrogen bonds to form a 3D supramolecular. Furthermore, catalytic oxidation activities toward organic dyes and electrochemical behaviors of the title complexes have been investigated at room temperature in aqueous solutions, indicating these complexes may be applicable to color removal in a textile wastewater stream and practical applications in areas of electrocatalytic reduction toward nitrite, respectively. - Graphical abstract: Two new coordination polymers based on different structural characteristics have been hydrothermally synthesized by the mixed ligands. The catalytic oxidation activities toward organic dyes and electrochemical behaviors of the title complexes have been investigated. - Highlights: • The organic ligand containing the tetrazolyl group and triazolyl group with some advantages has been used. • Two new coordination polymers with different structural characteristics has been discussed in detail. • Catalytic oxidation activities toward organic dyes and electrochemical behaviors of the title complexes have been investigated.« less

Sonochemical syntheses of a new nano-sized porous lead(II) coordination polymer as precursor for preparation of lead(II) oxide nanoparticles

NASA Astrophysics Data System (ADS)

Ranjbar, Zohreh Rashidi; Morsali, Ali

2009-11-01

Nano-scale of a new Pb(II) coordination polymer, {[Pb(bpacb)(OAc)]·DMF} n ( 1); bpacbH = 3,5-bis[(4-pyridylamino)carbonyl]benzoic acid], were synthesized by a sonochemical method. The nano-material was characterized by scanning electron microscopy, X-ray powder diffraction (XRD), 1H, 13C NMR, IR spectroscopy and elemental analyses. Crystal structure of compound 1 was determined by X-ray crystallography. Calcination of the nano-sized compound 1 at 700 °C under air atmospheres yields PbO nanoparticles. Thermal stability of nano-sized and single crystalline samples of compound 1 were studied and compared with each other.

A supramolecular miktoarm star polymer based on porphyrin metal complexation in water.

PubMed

Hou, Zhanyao; Dehaen, Wim; Lyskawa, Joël; Woisel, Patrice; Hoogenboom, Richard

2017-07-25

A novel supramolecular miktoarm star polymer was successfully constructed in water from a pyridine end-decorated polymer (Py-PmDEGA) and a metalloporphyrin based star polymer (ZnTPP-(PEG) 4 ) via metal-ligand coordination. The Py-PmDEGA moiety was prepared via a combination of reversible addition-fragmentation chain transfer polymerization (RAFT) and subsequent aminolysis and Michael addition reactions to introduce the pyridine end-group. The ZnTPP(PEG) 4 star-polymer was synthesized by the reaction between tetrakis(p-hydroxyphenyl)porphyrin and toluenesulfonyl-PEG, followed by insertion of a zinc ion into the porphyrin core. The formation of a well-defined supramolecular AB 4 -type miktoarm star polymer was unambiguously demonstrated via UV-Vis spectroscopic titration, isothermal titration calorimetry (ITC) and diffusion ordered NMR spectroscopy (DOSY).

Highly Sensitive Detection of UV Radiation Using a Uranium Coordination Polymer.

PubMed

Liu, Wei; Dai, Xing; Xie, Jian; Silver, Mark A; Zhang, Duo; Wang, Yanlong; Cai, Yawen; Diwu, Juan; Wang, Jian; Zhou, Ruhong; Chai, Zhifang; Wang, Shuao

2018-02-07

The accurate detection of UV radiation is required in a wide range of chemical industries and environmental or biological related applications. Conventional methods taking advantage of semiconductor photodetectors suffer from several drawbacks such as sophisticated synthesis and manufacturing procedure, not being able to measure the accumulated UV dosage as well as high defect density in the material. Searching for new strategies or materials serving as precise UV dosage sensor with extremely low detection limit is still highly desirable. In this work, a radiation resistant uranium coordination polymer [UO 2 (L)(DMF)] (L = 5-nitroisophthalic acid, DMF = N,N-dimethylformamide, denoted as compound 1) was successfully synthesized through mild solvothermal method and investigated as a unique UV probe with the detection limit of 2.4 × 10 -7 J. On the basis of the UV dosage dependent luminescence spectra, EPR analysis, single crystal structure investigation, and the DFT calculation, the UV-induced radical quenching mechanism was confirmed. Importantly, the generated radicals are of significant stability which offers the opportunity for measuring the accumulated UV radiation dosage. Furthermore, the powder material of compound 1 was further upgraded into membrane material without loss in luminescence intensity to investigate the real application potentials. To the best of our knowledge, compound 1 represents the most sensitive coordination polymer based UV dosage probe reported to date.

Strategies for the Construction of Supramolecular Dimers versus Homoleptic 1D Coordination Polymers Starting from the Diphosphorus [Cp2Mo2(CO)4(η2‐P2)] Complex and Silver(I) Salts

PubMed Central

Elsayed Moussa, Mehdi; Fleischmann, Martin; Peresypkina, Eugenia V.; Dütsch, Luis; Seidl, Michael; Balázs, Gabor

2017-01-01

The reactions of the tetrahedral diphosphorus [Cp2Mo2(CO)4(η2‐P2)] (1; Cp = C5H5) complex with Ag[Al{OC(CF3)3}4] (AgTEF) (A) and Ag[FAl{OC(C6F5)(C6F10)}3] (AgFAl) (B) were studied. The first reaction led to the formation of the [Ag2(η2‐1)2(η1:η1‐1)2][TEF]2 (2) dimer and the [Ag2(η1:η1‐1)3]n[TEF]2n (3) coordination polymer, whereas the second reaction afforded the [Ag2(η1:η1‐1)2(η1‐CH2Cl2)2(η2‐C7H8)2][FAl]2 (4) or the [Ag2(η2‐1)2(η1:η1‐1)2][FAl]2 (5) dimer and the [Ag2(η1:η1‐1)4]n[FAl]2n (6) coordination polymer. In each case, the products obtained depended on the ratio of the reactants and/or the synthetic procedure. PMID:28943780

Self-assembly of coordination polymers of Pr(III), Nd(III), Tb(III), Dy(III) and Ho(III) with 5-hydroxyisophthalic acid and adipic acid: Syntheses, structures, porosity, luminescence and magnetic properties

NASA Astrophysics Data System (ADS)

Kariem, Mukaddus; Yawer, Mohd; Kumar, Manesh; Nawaz Sheikh, Haq; Sood, Puneet; Kolekar, Sanjay S.

2017-11-01

Five novel coordination polymers (CPs) with the formula [Ln (hip) (adip)0.5(H2O)2]n. nH2O [Ln = Pr (1), Nd (2), Tb (3), Dy (4) and Ho (5)] were synthesized by self-organization of lanthanide salts with rigid [5-hydroxyisophthalic acid (H2hip)] and flexible [adipic acid (H2adip)] linkers under solvothermal condition. X-ray diffraction revealed data that all five CPs 1-5 are isostructural and crystallizes in monoclinic C2/c space group. Coordination polymers 1-5 exhibit 1D linear ladder shaped extension with the linkage of lanthanide carboxylate chains having the backbone of H2hip and H2adip ligands. The 1D linear ladder chains get transformed into three dimensional (3D) supramolecular network via non-covalent interactions (π-π and H - bonding). The porosity study showed that 20.34 mL of N2 gets adsorbed per 1.0 g of sample at 1 atm pressure. The CP 3 (Tb) and 4 (Dy) emit strong ligand sensitized characteristic f-f luminescence emission. The CPs 3 and 4 exhibit weak ferromagnetic interactions at lower temperatures.

Three d10 coordination polymers assembled from 3,5-bis(imidazole-1-yl)pyridine and different polycarboxylates: Syntheses, structures and luminescence properties

NASA Astrophysics Data System (ADS)

Pan, Jie; Zhang, Di; Xue, Zhen-Zhen; Wei, Li; Han, Song-De; Wang, Guo-Ming

2017-11-01

Three novel Zn(II)/Cd(II) coordination polymers, [Cd2(bip)2(m-bdc)2(H2O)2·3H2O]n (1), [Zn2(bip)2(p-bdc)2·2.5H2O]n (2) and [Zn(bip) (p-bdc)·3H2O]n (3), where bip = 3,5-bis(imidazole-1-yl)pyridine, m-H2bdc = 1,3-benzenedicarboxylic acid, p-H2bdc = 1,4-benzenedicarboxylic acid, have been successfully synthesized under solvothermal conditions. The linkage of different ligands with Cd(II) ions in compound 1 affords a (3,5)-connected layer. Furthermore, 2D→3D parallel polycatenation occurs wherein the layers are polycatenated with the adjacent two parallel layers to form a 3D framework. In 2 and 3, the polycarboxylates act as pillars to combine the metal-bip chains, yielding the layered structures. These 2D networks are extended to the final 3D supramolecular architectures by π-π stacking interactions. The results show that bip can act as a versatile building block for the construction of various coordination polymers. Moreover, the fluorescent properties of 1-3 in the solid state at room temperature have been investigated.

Structural Peculiarities of Ion-Conductive Organic-Inorganic Polymer Composites Based on Aliphatic Epoxy Resin and Salt of Lithium Perchlorate.

PubMed

Matkovska, Liubov; Iurzhenko, Maksym; Mamunya, Yevgen; Tkachenko, Igor; Demchenko, Valeriy; Synyuk, Volodymyr; Shadrin, Andriy; Boiteux, Gisele

2017-12-01

The article is concerned with hybrid amorphous polymers synthesized basing on epoxy oligomer of diglycide aliphatic ester of polyethylene glycol that was cured by polyethylene polyamine and lithium perchlorate salt. Structural peculiarities of organic-inorganic polymer composites were studied by differential scanning calorimetry, wide-angle X-ray spectra, infrared spectroscopic, scanning electron microscopy, elemental analysis, and transmission and reflective optical microscopy. On the one hand, the results showed that the introduction of LiClO 4 salt into epoxy polymer leads to formation of the coordinative metal-polymer complexes of donor-acceptor type between central Li + ion and ligand. On the other hand, the appearance of amorphous microinclusions, probably of inorganic nature, was also found.

Optimization of mechanical performance of oxidative nano-particle electrode nitrile butadiene rubber conducting polymer actuator.

PubMed

Kim, Baek-Chul; Park, S J; Cho, M S; Lee, Y; Nam, J D; Choi, H R; Koo, J C

2009-12-01

Present work delivers a systematical evaluation of actuation efficiency of a nano-particle electrode conducting polymer actuator fabricated based on Nitrile Butadiene Rubber (NBR). Attempts are made for maximizing mechanical functionality of the nano-particle electrode conducting polymer actuator that can be driven in the air. As the conducting polymer polypyrrole of the actuator is to be fabricated through a chemical oxidation polymerization process that may impose certain limitations on both electrical and mechanical functionality of the actuator, a coordinated study for optimization process of the actuator is necessary for maximizing its performance. In this article actuation behaviors of the nano-particle electrode polypyrrole conducting polymer is studied and an optimization process for the mechanical performance maximization is performed.

Interplay of non-Markov and internal friction effects in the barrier crossing kinetics of biopolymers: insights from an analytically solvable model.

PubMed

Makarov, Dmitrii E

2013-01-07

Conformational rearrangements in biomolecules (such as protein folding or enzyme-ligand binding) are often interpreted in terms of low-dimensional models of barrier crossing such as Kramers' theory. Dimensionality reduction, however, entails memory effects; as a result, the effective frictional drag force along the reaction coordinate nontrivially depends on the time scale of the transition. Moreover, when both solvent and "internal" friction effects are important, their interplay results in a highly nonlinear dependence of the effective friction on solvent viscosity that is not captured by common phenomenological models of barrier crossing. Here, these effects are illustrated using an analytically solvable toy model of an unstructured polymer chain involved in an inter- or intramolecular transition. The transition rate is calculated using the Grote-Hynes and Langer theories, which--unlike Kramers' theory--account for memory. The resulting effective frictional force exerted by the polymer along the reaction coordinate can be rationalized in terms of the effective number of monomers engaged in the transition. Faster transitions (relative to the polymer reconfiguration time scale) involve fewer monomers and, correspondingly, lower friction forces, because the polymer chain does not have enough time to reconfigure in response to the transition.

Four thiophene-pyridyl-amide-based Zn{sup II}/Cd{sup II} coordination polymers: Assembly, structures, photocatalytic properties and fluorescent recognition for Fe{sup 3+}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Xiu-Li; Wu, Xiao-Mei; Liu, Guo-Cheng

By tuning metal ions and combining with different dicarboxylates, four new semi-rigid thiophene-bis-pyridyl-bis-amide-based coordination polymers, namely, [Zn(3-bptpa)(1,3-BDC)]·DMA·2H{sub 2}O (1), [Zn(3-bptpa)(5-MIP)] (2), [Cd(3-bptpa)(1,3-BDC)]·2H{sub 2}O (3) and [Cd(3-bptpa)(5-MIP)]·4H{sub 2}O (4) (3-bptpa=N,N′-bis(pyridine-3-yl)thiophene-2,5-dicarboxamide, 1,3-H{sub 2}BDC=1,3-benzenedicarboxylic acid, 5-H{sub 2}MIP=5-methylisophthalic acid, DMA=N,N-dimethylacetamide), were solvothermally/hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction analyses, IR spectra, UV–vis diffuse-reflectance spectra (DRS), powder X-ray diffraction (PXRD) and thermal gravimetric analyses (TG). The structural analysis reveals that Zn-complexes 1 and 2 are similar 2D networks. While Cd-complexes 3 and 4 exhibit similar 2-fold interpenetrating 3D α-Po frameworks with the (4{sup 12}·6{sup 3}) topology. The photocatalytic properties for the degradation ofmore » methylene blue (MB) under ultraviolet light irradiation of the title complexes have been investigated in detail. Furthermore, the luminescent sensing behaviors for metal cations of 1–4 have been studied, the results indicate that 3 is an excellent fluorescent probe, with high sensitivity, selectivity, and simple regeneration, for environmentally relevant Fe{sup 3+} ions. - Graphical abstract: Four Zn{sup II}/Cd{sup II} coordination polymers with a thiophene-pyridyl-amide ligand have been prepared. The photocatalytic activities and fluorescent sensing properties for metal ions of the title complexes have been investigated. - Highlights: • Four coordination polymers with thiophene-pyridyl-amide ligands have been obtained. • The central metal ions play an important role in the formation of the frameworks. • The photoluminescent sensing and the photocatalytic properties have been investigated.« less

X-ray photoelectron study of Si+ ion implanted polymers

NASA Astrophysics Data System (ADS)

Tsvetkova, T.; Balabanov, S.; Bischoff, L.; Krastev, V.; Stefanov, P.; Avramova, I.

2010-11-01

X-ray photoelectron spectroscopy was used to characterize different polymer materials implanted with low energy Si+ ions (E=30 keV, D= 1.1017 cm-2). Two kinds of polymers were studied - ultra-high-molecular-weight poly-ethylene (UHMWPE), and poly-methyl-methacrylate (PMMA). The non-implanted polymer materials show the expected variety of chemical bonds: carbon-carbon, carbon being three- and fourfold coordinated, and carbon-oxygen in the case of PMMA samples. The X-ray photoelectron and Raman spectra show that Si+ ion implantation leads to the introduction of additional disorder in the polymer material. The X-ray photoelectron spectra of the implanted polymers show that, in addition to already mentioned bonds, silicon creates new bonds with the host elements - Si-C and Si-O, together with additional Si dangling bonds as revealed by the valence band study of the implanted polymer materials.

Computational modeling of in vitro biological responses on polymethacrylate surfaces

PubMed Central

Ghosh, Jayeeta; Lewitus, Dan Y; Chandra, Prafulla; Joy, Abraham; Bushman, Jared; Knight, Doyle; Kohn, Joachim

2011-01-01

The objective of this research was to examine the capabilities of QSPR (Quantitative Structure Property Relationship) modeling to predict specific biological responses (fibrinogen adsorption, cell attachment and cell proliferation index) on thin films of different polymethacrylates. Using 33 commercially available monomers it is theoretically possible to construct a library of over 40,000 distinct polymer compositions. A subset of these polymers were synthesized and solvent cast surfaces were prepared in 96 well plates for the measurement of fibrinogen adsorption. NIH 3T3 cell attachment and proliferation index were measured on spin coated thin films of these polymers. Based on the experimental results of these polymers, separate models were built for homo-, co-, and terpolymers in the library with good correlation between experiment and predicted values. The ability to predict biological responses by simple QSPR models for large numbers of polymers has important implications in designing biomaterials for specific biological or medical applications. PMID:21779132

Computational approach to the study of morphological properties of polymer/fullerene blends in photovoltaics

NASA Astrophysics Data System (ADS)

Gaitho, Francis M.; Mola, Genene T.; Pellicane, Giuseppe

2018-02-01

Organic solar cells have the ability to transform solar energy efficiently and have a promising energy balance. Producing these cells is economical and makes use of methods of printing using inks built on solvents that are well-matched with a variety of cheap materials like flexible plastic or paper. The primary materials used to manufacture organic solar cells include carbon-based semiconductors, which are good light absorbers and efficient charge generators. In this article, we review previous research of interest based on morphology of polymer blends used in bulk heterojunction (BHJ) solar cells and introduce their basic principles. We further review computational models used in the analysis of surface behavior of polymer blends in BHJ as well as the trends in the field of polymer surface science as applied to BHJ photovoltaics. We also give in brief, the opportunities and challenges in the area of polymer blends on BHJ organic solar cells.

Shape-tailored polymer colloids on the road to become structural motifs for hierarchically organized materials.

PubMed

Plüisch, Claudia Simone; Wittemann, Alexander

2013-12-01

Anisometric polymer colloids are likely to behave differently when compared with centrosymmetric particles. Their study may not only shine new light on the organization of matter; they may also serve as building units with specific symmetries and complexity to build new materials from them. Polymer colloids of well-defined complex geometries can be obtained by packing a limited number of spherical polymer particles into clusters with defined configurations. Such supracolloidal architectures can be fabricated at larger scales using narrowly dispersed emulsion droplets as templates. Assemblies built from at least two different types of particles as elementary building units open perspectives in selective targeting of colloids with specific properties, aiming for mesoscale building blocks with tailor-made morphologies and multifunctionality. Polymer colloids with defined geometries are also ideal to study shape-dependent properties such as the diffusion of complex particles. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Rapid and enhanced activation of microporous coordination polymers by flowing supercritical CO.sub.2

DOEpatents

Matzger, Adam J.; Liu, Baojian; Wong-Foy, Antek G.

2016-07-19

Flowing supercritical CO.sub.2 is used to activate metal organic framework materials (MOF). MOFs are activated directly from N,N-dimethylformamide (DMF) thus avoiding exchange with a volatile solvent. Most MCPs display increased surface areas directly after treatment although those with coordinatively unsaturated metal centers benefit from additional heating.

Synthesis, crystal structure, and luminescent properties of two coordination polymers based on 1,4-phenylenediacetic acid

NASA Astrophysics Data System (ADS)

Zhang, Meili; Ren, Yixia; Ma, Zhenzhen; Qiao, Lei

2017-06-01

Two coordination polymers, [Zn(pda)(bib)]n (1) and [Cd(pda)0.5(bib)Cl]n (2)]. (H2pda = 1,4-phenylenediacetic acid, bib = 1,2-bis(imidazol-1-ylmethyl)benzene), have been synthesized by using Zn(II)/Cd(II) salts with two flexible ligands pda and bib under hydrothermal conditions. Their structures have been characterized by elemental analysis, IR spectroscopy, single-crystal X-ray crystallography and powder X-ray diffraction (PXRD) analysis. Due to the coordination geometry around the metal ions and the diverse coordination modes of the flexible ligands, the obtained complex show diverse structures. In the structure of 1, a pair of bib ligands connect two Zn(II) atoms give rise a 22-membered ring, which is further extended by pda ligands in bidentate coordination mode leading a ring-containing 2D layer. In 2, bib ligands join [Cd2Cl2]2+ dimmers generate 1D polymeric ribbon, the pda ligands further extend such ribbon forming a 2D layer network containing rectangular windows, which discovers the effect of the central metal ions on the formation of metal-organic frameworks. In additional, luminescent properties of two complexes have also been studied, they could be potential fluorescence materials.

Autonomous self-healing structural composites with bio-inspired design

PubMed Central

D’Elia, Eleonora; Eslava, Salvador; Miranda, Miriam; Georgiou, Theoni K.; Saiz, Eduardo

2016-01-01

Strong and tough natural composites such as bone, silk or nacre are often built from stiff blocks bound together using thin interfacial soft layers that can also provide sacrificial bonds for self-repair. Here we show that it is possible exploit this design in order to create self-healing structural composites by using thin supramolecular polymer interfaces between ceramic blocks. We have built model brick-and-mortar structures with ceramic contents above 95 vol% that exhibit strengths of the order of MPa (three orders of magnitude higher than the interfacial polymer) and fracture energies that are two orders of magnitude higher than those of the glass bricks. More importantly, these properties can be fully recovered after fracture without using external stimuli or delivering healing agents. This approach demonstrates a very promising route towards the design of strong, ideal self-healing materials able to self-repair repeatedly without degradation or external stimuli. PMID:27146382

Autonomous self-healing structural composites with bio-inspired design.

PubMed

D'Elia, Eleonora; Eslava, Salvador; Miranda, Miriam; Georgiou, Theoni K; Saiz, Eduardo

2016-05-05

Strong and tough natural composites such as bone, silk or nacre are often built from stiff blocks bound together using thin interfacial soft layers that can also provide sacrificial bonds for self-repair. Here we show that it is possible exploit this design in order to create self-healing structural composites by using thin supramolecular polymer interfaces between ceramic blocks. We have built model brick-and-mortar structures with ceramic contents above 95 vol% that exhibit strengths of the order of MPa (three orders of magnitude higher than the interfacial polymer) and fracture energies that are two orders of magnitude higher than those of the glass bricks. More importantly, these properties can be fully recovered after fracture without using external stimuli or delivering healing agents. This approach demonstrates a very promising route towards the design of strong, ideal self-healing materials able to self-repair repeatedly without degradation or external stimuli.

Autonomous self-healing structural composites with bio-inspired design

NASA Astrophysics Data System (ADS)

D'Elia, Eleonora; Eslava, Salvador; Miranda, Miriam; Georgiou, Theoni K.; Saiz, Eduardo

2016-05-01

Strong and tough natural composites such as bone, silk or nacre are often built from stiff blocks bound together using thin interfacial soft layers that can also provide sacrificial bonds for self-repair. Here we show that it is possible exploit this design in order to create self-healing structural composites by using thin supramolecular polymer interfaces between ceramic blocks. We have built model brick-and-mortar structures with ceramic contents above 95 vol% that exhibit strengths of the order of MPa (three orders of magnitude higher than the interfacial polymer) and fracture energies that are two orders of magnitude higher than those of the glass bricks. More importantly, these properties can be fully recovered after fracture without using external stimuli or delivering healing agents. This approach demonstrates a very promising route towards the design of strong, ideal self-healing materials able to self-repair repeatedly without degradation or external stimuli.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, Qianqian; Han, Ying; Lin, Hechun, E-mail: hclin@ee.ecnu.edu.cn

One dimensional coordination polymer Gd[(SO{sub 4})(NO{sub 3})(C{sub 2}H{sub 6}SO){sub 2}] (1) is prepared through the mediation of Bronsted acid ionic liquid, which crystallized in the monoclinic space of C2/c. In this polymer, adjacent Gd atoms are linked by two SO{sub 4}{sup 2-} ions to generate a 1-D chain, and all oxygen atoms in SO{sub 4}{sup 2-} groups are connected to three nearest Gd atoms in µ{sup 3}:η{sup 1}:η{sup 1}:η{sup 2} fashion. Gd, S and N from SO{sub 4}{sup 2-} and NO{sub 3}{sup -} are precisely coplanar. The planar is coordinated by a pair of DMSO molecules, which is parallel andmore » linked by hydrogen bonding to form a three-dimensional supramolecular network. Magnetic susceptibility measurement of 1 reveals weak antiferromagnetic interactions between the Gd (III) ions. It exhibits relatively large magneto-caloric effect with –ΔS{sub m}=28.8 J Kg{sup −1} K{sup −1} for ΔH=7 T. - Graphical abstract: Coordination polymer Gd[(SO{sub 4})(NO{sub 3})(C{sub 2}H{sub 6}SO){sub 2}] was obtained mediated by Bronsted acid Ionic Liquid, which presents a 1-D chains collected by SO{sub 4}{sup 2-} groups. Magnetic susceptibility of the polymer reveals weak antiferromagnetic interactions between the Gd(III) ions with the relatively large magneto-caloric effect of –ΔS{sub m}=28.8 J Kg{sup −1} K{sup −1} for ΔH= 7T.« less

XAFS investigation of polyamidoxime-bound uranyl contests the paradigm from small molecule studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mayes, Richard T.; Piechowicz, Marek; Lin, Zekai

In this study, limited resource availability and population growth have motivated interest in harvesting valuable metals from unconventional reserves, but developing selective adsorbents for this task requires structural knowledge of metal binding environments. Amidoxime polymers have been identified as the most promising platform for large-scale extraction of uranium from seawater. However, despite more than 30 years of research, the uranyl coordination environment on these adsorbents has not been positively identified. We report the first XAFS investigation of polyamidoxime-bound uranyl, with EXAFS fits suggesting a cooperative chelating model, rather than the tridentate or η 2 motifs proposed by small molecule andmore » computational studies. Samples exposed to environmental seawater also display a feature consistent with a μ 2-oxo-bridged transition metal in the uranyl coordination sphere, suggesting in situ formation of a specific binding site or mineralization of uranium on the polymer surface. These unexpected findings challenge several long-held assumptions and have significant implications for development of polymer adsorbents with high selectivity.« less

A single particle model to simulate the dynamics of entangled polymer melts.

PubMed

Kindt, P; Briels, W J

2007-10-07

We present a computer simulation model of polymer melts representing each chain as one single particle. Besides the position coordinate of each particle, we introduce a parameter n(ij) for each pair of particles i and j within a specified distance from each other. These numbers, called entanglement numbers, describe the deviation of the system of ignored coordinates from its equilibrium state for the given configuration of the centers of mass of the polymers. The deviations of the entanglement numbers from their equilibrium values give rise to transient forces, which, together with the conservative forces derived from the potential of mean force, govern the displacements of the particles. We have applied our model to a melt of C(800)H(1602) chains at 450 K and have found good agreement with experiments and more detailed simulations. Properties addressed in this paper are radial distribution functions, dynamic structure factors, and linear as well as nonlinear rheological properties.

XAFS investigation of polyamidoxime-bound uranyl contests the paradigm from small molecule studies

DOE PAGES

Mayes, Richard T.; Piechowicz, Marek; Lin, Zekai; ...

2015-11-12

In this study, limited resource availability and population growth have motivated interest in harvesting valuable metals from unconventional reserves, but developing selective adsorbents for this task requires structural knowledge of metal binding environments. Amidoxime polymers have been identified as the most promising platform for large-scale extraction of uranium from seawater. However, despite more than 30 years of research, the uranyl coordination environment on these adsorbents has not been positively identified. We report the first XAFS investigation of polyamidoxime-bound uranyl, with EXAFS fits suggesting a cooperative chelating model, rather than the tridentate or η 2 motifs proposed by small molecule andmore » computational studies. Samples exposed to environmental seawater also display a feature consistent with a μ 2-oxo-bridged transition metal in the uranyl coordination sphere, suggesting in situ formation of a specific binding site or mineralization of uranium on the polymer surface. These unexpected findings challenge several long-held assumptions and have significant implications for development of polymer adsorbents with high selectivity.« less

Main-chain metallopolymers at the static-dynamic boundary based on nickelocene

NASA Astrophysics Data System (ADS)

Musgrave, Rebecca A.; Russell, Andrew D.; Hayward, Dominic W.; Whittell, George R.; Lawrence, Paul G.; Gates, Paul J.; Green, Jennifer C.; Manners, Ian

2017-08-01

Interactions between metal ions and ligands in metal-containing polymers involve two bonding extremes: persistent covalent bonding, in which the polymers are essentially static in nature, or labile coordination bonding, which leads to dynamic supramolecular materials. Main-chain polymetallocenes based on ferrocene and cobaltocene fall into the former category because of the presence of strong metal-cyclopentadienyl bonds. Herein, we describe a main-chain polynickelocene—formed by ring-opening polymerization of a moderately strained [3]nickelocenophane monomer—that can be switched between static and dynamic states because of the relatively weak nickel-cyclopentadienyl ligand interactions. This is illustrated by the observation that, at a low concentration or at an elevated temperature in a coordinating or polar solvent, depolymerization of the polynickelocene occurs. A study of this dynamic polymer-monomer equilibrium by 1H NMR spectroscopy allowed the determination of the associated thermodynamic parameters. Microrheology data, however, indicated that under similar conditions the polynickelocene is considered to be static on the shorter rheological timescale.

A new synthesis route for Os-complex modified redox polymers for potential biofuel cell applications.

PubMed

Pöller, Sascha; Beyl, Yvonne; Vivekananthan, Jeevanthi; Guschin, Dmitrii A; Schuhmann, Wolfgang

2012-10-01

A new synthesis route for Os-complex modified redox polymers was developed. Instead of ligand exchange reactions for coordinative binding of suitable precursor Os-complexes at the polymer, Os-complexes already exhibiting the final ligand shell containing a suitable functional group were bound to the polymer via an epoxide opening reaction. By separation of the polymer synthesis from the ligand exchange reaction at the Os-complex, the modification of the same polymer backbone with different Os-complexes or the binding of the same Os-complex to a number of different polymer backbones becomes feasible. In addition, the Os-complex can be purified and characterized prior to its binding to the polymer. In order to further understand and optimize suitable enzyme/redox polymer systems concerning their potential application in biosensors or biofuel cells, a series of redox polymers was synthesized and used as immobilization matrix for Trametes hirsuta laccase. The properties of the obtained biofuel cell cathodes were compared with similar biocatalytic interfaces derived from redox polymers obtained via ligand exchange reaction of the parent Os-complex with a ligand integrated into the polymer backbone during the polymer synthesis. Copyright © 2011 Elsevier B.V. All rights reserved.

Pressure-induced amorphization of a dense coordination polymer and its impact on proton conductivity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Umeyama, Daiki; Hagi, Keisuke; Ogiwara, Naoki

2014-12-01

The proton conductivity of a dense coordination polymer (CP) was investigated under high-pressure conditions. Impedance measurements under high pressures revealed that the proton conductivity of the CP decreased more than 1000-fold at pressures of 3–7 GPa and that the activation energy for proton conduction almost doubled compared with that at ambient pressure. A synchrotron X-ray study under high pressure identified the amorphization process of the CP during compression, which rationally explains the decrease in conductivity and increase in activation energy. This phenomenon is categorized as reversible pressure-induced amorphization of a dense CP and is regarded as a demonstration of themore » coupling of the mechanical and electrical properties of a CP.« less

Formation of Foam-like Microstructural Carbon Material by Carbonization of Porous Coordination Polymers through a Ligand-Assisted Foaming Process.

PubMed

Kongpatpanich, Kanokwan; Horike, Satoshi; Fujiwara, Yu-Ichi; Ogiwara, Naoki; Nishihara, Hirotomo; Kitagawa, Susumu

2015-09-14

Porous carbon material with a foam-like microstructure has been synthesized by direct carbonization of porous coordination polymer (PCP). In situ generation of foaming agents by chemical reactions of ligands in PCP during carbonization provides a simple way to create lightweight carbon material with a foam-like microstructure. Among several substituents investigated, the nitro group has been shown to be the key to obtain the unique foam-like microstructure, which is due to the fast kinetics of gas evolution during carbonization. Foam-like microstructural carbon materials showed higher pore volume and specific capacitance compared to a microporous carbon. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

"Plug and play" logic gates based on fluorescence switching regulated by self-assembly of nucleotide and lanthanide ions.

PubMed

Pu, Fang; Ren, Jinsong; Qu, Xiaogang

2014-06-25

Molecular logic gates in response to chemical, biological, or optical input signals at a molecular level have received much interest over the past decade. Herein, we construct "plug and play" logic systems based on the fluorescence switching of guest molecules confined in coordination polymer nanoparticles generated from nucleotide and lanthanide ions. In the system, the addition of new modules directly enables new logic functions. PASS 0, YES, PASS 1, NOT, IMP, OR, and AND gates are successfully constructed in sequence. Moreover, different logic gates (AND, INH, and IMP) can be constructed using different guest molecules and the same input combinations. The work will be beneficial to the future logic design and expand the applications of coordination polymers.

Employing linear tetranuclear [Zn4(COO)4(OH)2] clusters as building subunits to construct a new Zn(II) coordination polymer with tunable luminescent properties

NASA Astrophysics Data System (ADS)

Li, Wu-Wu; Zhang, Zun-Ting

2016-02-01

A new Zn(II) coordination polymer, [Zn2(btc) (biimpy) (OH)]n (1 H3btc = 1,3,5-benzenetricarboxylic acid, biimpy = 2,6-bis(1-imdazoly)pyridine) has been successfully synthesized and characterized by elemental analysis, powder single crystal X-ray diffraction analyses. Compound 1 features a 3D framework employing linear tetranuclear [Zn4(COO)4(OH)2] cluster as building subunits. Topological analysis reveals it represents a (3,10)-connected structural topology by viewing btc3-, linear tetranuclear clusters and biimpy as 3-connected nodes, 10-connected nodes, linear linkers, respectively. Moreover, the thermal stability and luminescent property of compound 1 have been well investigated.

Interphase Transformations at Metal (Copper, Iron)-Polymer Gel-Electrolyte Interfaces

NASA Astrophysics Data System (ADS)

Lyamina, G. V.; Dubinina, O. V.; Vaitulevich, E. A.; Mokrousov, G. M.

2018-07-01

The results from studies of the interface boundaries between metals (copper and iron) and gel electrolyte based on methacrylic copolymers are organized systematically. In contrast to processes in liquid electrolytes, a number of key features of the reactions that occur at such interfaces are revealed: a diffusion limiting stage; a lack of reverse reactions; and the formation of coordination compounds of metal ions with the functional groups of polymers, the stabilities of which are several orders of magnitude greater than that of coordination with their low-molecular weight counterparts. It is shown that processes which employ polymeric organogels can be used for the careful cleaning of the metal surfaces, and for the formation of a desired phase composition on the latter.

Syntheses, structures and photoluminescence properties of three M(II)-coordination polymers (M dbnd Zn(II), Mn(II)) based on a pyridine N-oxide bridging ligand

NASA Astrophysics Data System (ADS)

Ren, Xiu-Hui; Wang, Peng; Cheng, Jun-Yan; Dong, Yu-Bin

2018-06-01

Three M(II)-coordination polymers (M dbnd Zn(II), Mn(II)) were synthesized based on a pyridine N-oxide bridging ligand 3,5-bis(4-carboxylphenyl)-pyridine N-oxide (L1). Compounds 1-3 all have novel complicated structures. Compound 1 (Zn(L1)2(H2O)2) and 2 (Zn2(L1)2(H2O)2) are two single crystals obtained in "one pot" and 1 features 1D double chains motif and 2 features 3D network structure. Compound 3 shows 3D network structure with triangular tunnels. The thermogravimetric analyses and photoluminescence properties were also used to investigate the title compounds.

Colloid-polymer mixtures under slit confinement.

PubMed

Pérez-Ramírez, Allan; Figueroa-Gerstenmaier, Susana; Odriozola, Gerardo

2017-03-14

We report a NVT molecular dynamic study of colloid-polymer mixtures under slit confinement. For this purpose, we are employing the Asakura-Oosawa model for studying colloidal particles, polymer coils, and hard walls as the external confining field. The colloid-polymer size ratio, q, is varied in the range 1⩾q⩾0.4 and the confinement distance, H, in 10σ c ⩾H⩾3σ c , σ c being the colloidal diameter. Vapor-liquid coexistence properties are assessed, from which phase diagrams are built. The obtained data fulfill the corresponding states law for a constant H when q is varied. The shift of the polymer and colloidal chemical potentials of coexistence follows a linear relationship with (H-σ c ) -1 for H≳4σ c . The confined vapor-liquid interfaces can be fitted with a semicircular line of curvature (H-σ c ) -1 , from which the contact angle can be obtained. We observe complete wetting of the confining walls for reservoir polymer concentrations above and close to the critical value, and partial wetting for reservoir polymer concentrations above and far from it.

Colloid-polymer mixtures under slit confinement

NASA Astrophysics Data System (ADS)

Pérez-Ramírez, Allan; Figueroa-Gerstenmaier, Susana; Odriozola, Gerardo

2017-03-01

We report a NVT molecular dynamic study of colloid-polymer mixtures under slit confinement. For this purpose, we are employing the Asakura-Oosawa model for studying colloidal particles, polymer coils, and hard walls as the external confining field. The colloid-polymer size ratio, q, is varied in the range 1 ⩾q ⩾0.4 and the confinement distance, H, in 10 σc ⩾H ⩾3 σc , σc being the colloidal diameter. Vapor-liquid coexistence properties are assessed, from which phase diagrams are built. The obtained data fulfill the corresponding states law for a constant H when q is varied. The shift of the polymer and colloidal chemical potentials of coexistence follows a linear relationship with (H-σc ) -1 for H ≳4 σc . The confined vapor-liquid interfaces can be fitted with a semicircular line of curvature (H-σc ) -1, from which the contact angle can be obtained. We observe complete wetting of the confining walls for reservoir polymer concentrations above and close to the critical value, and partial wetting for reservoir polymer concentrations above and far from it.

Redox electrodeposition polymers: adaptation of the redox potential of polymer-bound Os complexes for bioanalytical applications.

PubMed

Guschin, Dmitrii A; Castillo, John; Dimcheva, Nina; Schuhmann, Wolfgang

2010-10-01

The design of polymers carrying suitable ligands for coordinating Os complexes in ligand exchange reactions against labile chloro ligands is a strategy for the synthesis of redox polymers with bound Os centers which exhibit a wide variation in their redox potential. This strategy is applied to polymers with an additional variation of the properties of the polymer backbone with respect to pH-dependent solubility, monomer composition, hydrophilicity etc. A library of Os-complex-modified electrodeposition polymers was synthesized and initially tested with respect to their electron-transfer ability in combination with enzymes such as glucose oxidase, cellobiose dehydrogenase, and PQQ-dependent glucose dehydrogenase entrapped during the pH-induced deposition process. The different polymer-bound Os complexes in a library containing 50 different redox polymers allowed the statistical evaluation of the impact of an individual ligand to the overall redox potential of an Os complex. Using a simple linear regression algorithm prediction of the redox potential of Os complexes becomes feasible. Thus, a redox polymer can now be designed to optimally interact in electron-transfer reactions with a selected enzyme.

JTEC monograph on biodegradable polymers and plastics in Japan: Research, development, and applications

NASA Technical Reports Server (NTRS)

Lenz, Robert W.

1995-01-01

A fact-finding team of American scientists and engineers visited Japan to assess the status of research and development and applications in biodegradable polymers. The visit was sponsored by the National Science Foundation and industry. In Japan, the team met with representatives of 31 universities, government ministries and institutes, companies, and associations. Japan's national program on biodegradable polymers and plastics evaluates new technologies, testing methods, and potential markets for biodegradables. The program is coordinated by the Biodegradable Plastics Society of Japan, which seeks to achieve world leadership in biodegradable polymer technology and identify commercial opportunities for exploiting this technology. The team saw no major new technology breakthroughs. Japanese scientists and engineers are focusing on natural polymers from renewable resources, synthetic polymers, and bacterially-produced polymers such as polyhydroxyalkanoates, poly(amino acids), and polysaccharides. The major polymers receiving attention are the Zeneca PHBV copolymers, Biopol(registered trademark), poly(lactic acid) from several sources, polycaprolactone, and the new synthetic polyester, Bionolle(registered trademark), from Showa High Polymer. In their present state of development, these polymers all have major deficiencies that inhibit their acceptance for large-scale applications.

Corrosion evaluation of mechanically stabilized earth walls.

DOT National Transportation Integrated Search

2005-09-01

Numerous reinforced walls and slopes have been built over the past four decades in Kentucky, the United States, as well as worldwide. Tensile elements used in constructing low-cost reinforcing walls and slopes consist of metal polymer strips or grids...

Homoleptic ligands vs heteroleptic ligands on coordination polymerizations: Construction and properties of silver(I) coordination polymers containing dialkylbis(4-pyridy)silanes

NASA Astrophysics Data System (ADS)

Park, Minwoo; Jang, Jaeseong; Moon, So Yun; Jung, Ok-Sang

2014-03-01

Investigations into pure bidentate ligand vs mixed bidentate ligands on self-assembly of AgPF6 with the respective L1, L2, L3, L1/L2, L1/L3, and L2/L3 (L1 = diethylbis(4-pyridyl)silane; L2 = ethylmethylbis(4-pyridyl)silane; L3 = cyclotetramethylenebis(4-pyridyl)silane) were carried out. The self-assembly reactions of AgPF6 with the respective ligand system produce desirable homoleptic or heteroleptic silver(I) coordination polymers. [Ag(L1)2](PF6) gives rise to a tubular loop chain whereas the other five products lead to a twofold interpenetration diamonoid structure. [Ag(L1)2](PF6) shows a strong blue luminescence at 453 nm (λex = 270 nm), which is useful to recognize alcohols. All products were characterized by thermal analyses, and in particular, calcination of [Ag(L3)2](PF6)ṡCH3OH at 600 °C finally produces silver(0) microcrystalline morphology.

First examples of ternary lanthanide 5-aminoisophthalate complexes: Hydrothermal syntheses and structures of lanthanide coordination polymers with 5-aminoisophthalate and oxalate

NASA Astrophysics Data System (ADS)

Liu, Chong-Bo; Wen, Hui-Liang; Tan, Sheng-Shui; Yi, Xiu-Guang

2008-05-01

Two new lanthanide coordination polymers with mixed-carboxylates, [Ln(OX)(HAPA)(H 2O)] n[Ln = Eu ( 1), Ho ( 2); H 2APA = 5-aminoisophthalic acid; OX = oxalate] were obtained by hydrothermal reactions, and characterized by single crystal X-ray diffraction, elemental analysis and IR spectra. Complexes 1 and 2 are both 3-D supramolecular structure, in which lanthanide ions are bridged by oxalate and 5-aminoisophthalate ligands forming 2-D metal-organic framework, and 2-D networks are further architectured to form 3-D supramolecular structures by hydrogen bonds. The two carboxylate groups of H 2APA ligand are all deprotonated and exhibit chelating and bridging bidentate coordination modes, respectively, and the amino group in HAPA presents - NH3+ in the titled complexes. The thermogravimetric analysis was carried out to examine the thermal stability of the titled complexes. And the photoluminescence property of 1 was investigated.

catena-Poly[[[triaqua­sulfatozinc(II)]-μ-3,3′-bis­(3-pyrid­yl)-1,1′-(m-phenyl­ene)diurea] methanol solvate monohydrate

PubMed Central

Adarsh, N. N.; Dastidar, Parthasarathi

2010-01-01

In the title coordination polymer, {[Zn(SO4)(C18H16N6O2)(H2O)3]·CH3OH·H2O}n, the Zn2+ ion adopts a slightly distorted cis-ZnN2O4 octa­hedral geometry arising from three coordinated water mol­ecules, one sulfate ion and two bridging 3,3′-bis­(3-pyrid­yl)-1,1′-(m-phenyl­ene)diurea (bpmpbu) ligands. The dihedral angles between the central benzene ring and two terminal pyridine rings of the bpmbpu mol­ecule are 10.58 (17) and 34.63 (16)°. In the crystal, the ligands bridge the ZnII ions, thus generating a one-dimensional zigzag coordination polymer propagating in [010]. The crystal structure features extensive N—H⋯O and O—H⋯O hydrogen-bonding inter­actions. PMID:21580512

Gram-scale synthesis of coordination polymer nanodots with renal clearance properties for cancer theranostic applications

NASA Astrophysics Data System (ADS)

Liu, Fuyao; He, Xiuxia; Chen, Hongda; Zhang, Junping; Zhang, Huimao; Wang, Zhenxin

2015-08-01

An ultrasmall hydrodynamic diameter is a critical factor for the renal clearance of nanoparticles from the body within a reasonable timescale. However, the integration of diagnostic and therapeutic components into a single ultrasmall nanoparticle remains challenging. In this study, pH-activated nanodots (termed Fe-CPNDs) composed of coordination polymers were synthesized via a simple and scalable method based on coordination reactions among Fe3+, gallic acid and poly(vinylpyrrolidone) at ambient conditions. The Fe-CPNDs exhibited ultrasmall (5.3 nm) hydrodynamic diameters and electrically neutral surfaces. The Fe-CPNDs also exhibited pH-activatable magnetic resonance imaging contrast and outstanding photothermal performance. The features of Fe-CPNDs greatly increased the tumour-imaging sensitivity and facilitated renal clearance after injection in animal models in vivo. Magnetic resonance imaging-guided photothermal therapy using Fe-CPNDs completely suppressed tumour growth. These findings demonstrate that Fe-CPNDs constitute a new class of renal clearable nanomedicine for photothermal therapy and molecular imaging.

Solvothermal synthesis and structural characterization of a three-dimensional metal organic polymer [NaZn(1,2,4-BTC)] (1,2,4-BTC=1,2,4-benzenetricarboxylate)

NASA Astrophysics Data System (ADS)

Wang, Lei; Shi, Zhan; Li, Guanghua; Fan, Yong; Fu, Wensheng; Feng, Shouhua

2004-01-01

A new three-dimensional metal-organic polymer, [NaZn(1,2,4-BTC)] (where 1,2,4-BTC=1,2,4-benzenetricarboxylate), has been prepared under solvothermal conditions and characterized by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P2 1/ c, with cell parameters: a=9.7706(4) Å, b=12.3549(5) Å, c=6.8897(3) Å, β=91.640(2)°, V=831.35(6) Å 3 and Z=4. In the three-dimensional structure of the compound, each Zn atom is five-coordinated in distorted trigonal bipyramidal geometry, while the sixfold coordination of Na corresponds to a slightly distorted triangular prism. The organic ligand, 1,2,4-BTC, shows a novel and unprecedented coordination mode: 11 bonds to 10 metals with each carboxylate function exhibiting different linkages. It remains stable when desolvated and when heated up to 410 °C.

A one-dimensional nickel(II) coordination polymer containing 2,6-dipicolinate and dipyrido[3,2-a:2',3'-c]phenazine.

PubMed

Ma, Yi; Zhang, Li-Tian; Wang, Xiao-Fang; He, Yong-Ke; Han, Zheng-Bo

2007-12-01

A new coordination polymer, catena-poly[[(dipyrido[3,2-a:2',3'-c]phenazine-kappa(2)N,N')nickel(II)]-mu-2,6-dipicolinato-kappa(4)O(2),N,O(6):O(2')], [Ni(C7H3NO4)(C18H10N4)]n, exhibits a one-dimensional structure in which 2,6-dipicolinate acts as a bridging ligand interconnecting adjacent nickel(II) centers to form a chain structure. The asymmetric unit contains one Ni(II) center, one dipyrido[3,2-a:2',3'-c]phenazine ligand and one 2,6-dipicolinate ligand. Each Ni(II) center is six-coordinated and surrounded by three N atoms and three O atoms from one dipyrido[3,2-a:2',3'-c]phenazine ligand and two different 2,6-dipicolinate ligands, leading to a distorted octahedral geometry. Adjacent chains are linked by pi-pi stacking interactions and weak interactions to form a three-dimensional supramolecular network.

A conjugated microporous polymer based visual sensing platform for aminoglycoside antibiotics in water.

PubMed

Bhunia, Subhajit; Dey, Nilanjan; Pradhan, Anirban; Bhattacharya, Santanu

2018-06-20

A donor-acceptor based conjugated microporous polymer, PER@NiP-CMOP-1, has been synthesized which can achieve highly sensitive stereo-specific "Turn ON" biosensing of an aminoglycoside up to the ppb level. The coordination-driven inhibition of photo-induced electron transfer (d-PET) for d-electrons and the rotational freezing are the key factors for the recovery of the emission.

Rare earth niobate coordination polymers

NASA Astrophysics Data System (ADS)

Muniz, Collin N.; Patel, Hiral; Fast, Dylan B.; Rohwer, Lauren E. S.; Reinheimer, Eric W.; Dolgos, Michelle; Graham, Matt W.; Nyman, May

2018-03-01

Rare-earth (RE) coordination polymers are infinitely tailorable to yield luminescent materials for various applications. Here we described the synthesis of a heterometallic rare-earth coordination compound ((CH3)2SO)3(RE)NbO(C2O4)3((CH3)2SO) = dimethylsulfoxide, DMSO, (C2O2= oxalate), (RE=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb). The structure was obtained from single crystal X-ray diffraction of the La analogue. The Nb˭O and DMSO terminal-bonding character guides assembly of an open framework structure with noncentrosymmetric RE-coordination geometry, and large spacing between the RE centers. A second structure was observed by PXRD for the smaller rare earths (Dy, Ho, Er, Yb); this structure has not yet been determined. The materials were further characterized using FTIR, and photoluminescence measurements. Characteristic excitation and emission transitions were observed for RE = Nd, Sm, Eu, and Tb. Quantum yield (QY) measurements were performed by exciting Eu and Tb analoges at 394 nm (QY 66%) and 464 nm (QY 71%) for Eu; and 370 nm (QY=40%) for Tb. We attribute the high QY and bright luminescence to two main structure-function properties of the system; namely the absence of water in the structure, and absence of concentration quenching.

Construction and Self-Assembly of Single-Chain Polymer Nanoparticles via Coordination Association and Electrostatic Repulsion in Water.

PubMed

Zhu, Zhengguang; Xu, Na; Yu, Qiuping; Guo, Lei; Cao, Hui; Lu, Xinhua; Cai, Yuanli

2015-08-01

Simultaneous coordination-association and electrostatic-repulsion interactions play critical roles in the construction and stabilization of enzymatic function metal centers in water media. These interactions are promising for construction and self-assembly of artificial aqueous polymer single-chain nanoparticles (SCNPs). Herein, the construction and self-assembly of dative-bonded aqueous SCNPs are reported via simultaneous coordination-association and electrostatic-repulsion interactions within single chains of histamine-based hydrophilic block copolymer. The electrostatic-repulsion interactions are tunable through adjusting the imidazolium/imidazole ratio in response to pH, and in situ Cu(II)-coordination leads to the intramolecular association and single-chain collapse in acidic water. SCNPs are stabilized by the electrostatic repulsion of dative-bonded block and steric shielding of nonionic water-soluble block, and have a huge specific surface area of function metal centers accessible to substrates in acidic water. Moreover, SCNPs can assemble into micelles, networks, and large particles programmably in response to the solution pH. These unique media-sensitive phase-transformation behaviors provide a general, facile, and versatile platform for the fabrication of enzyme-inspired smart aqueous catalysts. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

New Mononuclear Cu(II) Complexes and 1D Chains with 4-Amino-4H-1,2,4-triazole

PubMed Central

Dîrtu, Marinela M.; Boland, Yves; Gillard, Damien; Tinant, Bernard; Robeyns, Koen; Safin, Damir A.; Devlin, Eamonn; Sanakis, Yiannis; Garcia, Yann

2013-01-01

The crystal structures of two mononuclear Cu(II) NH2trz complexes [Cu(NH2trz)4(H2O)](AsF6)2 (I) and [Cu(NH2trz)4(H2O)](PF6)2 (II) as well as two coordination polymers [Cu(μ2-NH2trz)2Cl]Cl·H2O (III) and [Cu(μ2-NH2trz)2Cl] (SiF6)0.5·1.5H2O (IV) are presented. Cationic 1D chains with bridging bis-monodentate μ2-coordinated NH2trz and bridging μ2-coordinated chloride ligands are present in III and IV. In these coordination polymers, the Cu(II) ions are strongly antiferromagnetically coupled with J = −128.4 cm−1 for III and J = −143 cm−1 for IV (H = −J∑SiSi+1), due to the nature of the bridges between spin centers. Inter-chain interactions present in the crystal structures were taken into consideration, as well as g factors, which were determined experimentally, for the quantitative modeling of their magnetic properties. PMID:24300095

Recovery of Uranium from Seawater: Preparation and Development of Polymer-Supported Extractants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spiro, Alexandratos

2013-12-01

A new series of polymer-supported extractants is proposed for the removal and recovery of uranium from seawater. The objective is to produce polymers with improved stability, loading capacity, and sorption kinetics compared to what is found with amidoximes. The target ligands are diphosphonates and aminomethyldiphosphonates. Small molecule analogues, especially of aminomethyldiphos-phonates, have exceptionally high stability constants for the uranyl ion. The polymeric diphosphonates will have high affinities due to their ability to form six-membered rings with the uranyl ion while the aminomethyldiphosphonates may have yet higher affinities due to possible tridentate coordination and their greater acidity. A representative set ofmore » the polymers to be prepared are indicated.« less

A low-cost photonic biosensor built on a polymer platform

NASA Astrophysics Data System (ADS)

Wang, Linghua; Kodeck, Valérie; Van Vlierberghe, Sandra; Ren, Jun; Teng, Jie; Han, Xiuyou; Jian, Xigao; Baets, Roel; Morthier, Geert; Zhao, Mingshan

2011-12-01

Planar integrated optical biosensors are becoming more and more important as they facilitate label-free and real time monitoring biosensing with high sensitivity. In this paper, the systematic research on one kind of optical biosensor, based on a resonant principle in a polymer ring resonator, will be presented. Reduced footprint and high sensitivity are advantages of this kind of biosensor. Rather than expensive CMOS fabrication, the device with high performance is fabricated through a simple UV based soft imprint technique utilizing self-developed low loss polymer material. The measurement results for the bulk sensing of a NaCl solution and the surface sensing of a minimal amount of avidin molecules in a buffered solution will be presented.

Lanthanide co-ordination frameworks: Opportunities and diversity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hill, Robert J.; Long, De-Liang; Hubberstey, Peter

2005-08-15

Significant successes have been made over recent years in preparing co-ordination framework polymers that show macroscopic material properties, but in the vast majority of cases this has been achieved with d-block metal-based systems. Lanthanide co-ordination frameworks also offer attractive properties in terms of their potential applications as luminescent, non-linear optical and porous materials. However, lanthanide-based systems have been far less studied to date than their d-block counterparts. One possible reason for this is that the co-ordination spheres of lanthanide cations are more difficult to control and, in the absence of design strategies for lanthanide co-ordination frameworks, it is significantly moremore » difficult to target materials with specific properties. However, this article highlights some of the exciting possibilities that have emerged from the earliest investigations in this field with new topological families of compounds being discovered from relatively simple framework components, including unusual eight, seven and five-connected framework systems. Our own research, as well as others, is leading to a much greater appreciation of the factors that control framework formation and the resultant observed topologies of these polymers. As this understanding develops targeting particular framework types will become more straightforward and the development of designed polyfunctional materials more accessible. Thus, it can be seen that lanthanide co-ordination frameworks have the potential to open up previously unexplored directions for materials chemistry. This article focuses on the underlying concepts for the construction of these enticing and potentially highly important materials.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tang, Chunying; Lu, Jialin; Han, Jingyu

Polymeric lanthanide complexes with thiostannate and polyamine mixed ligands, [Ln(peha)(μ–SnS{sub 4}H)]{sub n} [Ln=La (1a), Nd (1b)] and [(Ln(tepa)(μ–OH)){sub 2}(μ–Sn{sub 2}S{sub 6})]{sub n}nH{sub 2}O [Ln=Nd (2a), Sm (2b), Gd (2c), Dy (2d)] (peha=pentaethylenehexamine, tepa=tetraethylenepentamine) were respectively prepared in peha and tepa coordinative solvents by the solvothermal methods. In 1a and 1b, the Ln{sup 3+} ions are coordinated by a hexadentate peha ligand forming [Ln(peha)]{sup 3+} units. The [SnS{sub 4}H]{sup 3−} anion chelates a [Ln(peha)]{sup 3+} unit via two S atoms and coordinates to another [Ln(peha)]{sup 3+} unit via the third S atom. As a result, the [Ln(peha)]{sup 3+} units are connectedmore » into coordination polymers [Ln(peha)(μ–SnS{sub 4}H)]{sub n} by an unprecedented tridentate μ–η{sup 1},η{sup 2}–SnS{sub 4}H bridging ligands. In 2a–2d, the Ln{sup 3+} ions are coordinated by a pentadentate tepa ligand, and two [Ln(tepa)]{sup 3+} units are joined by two μ–OH bridges to form a binuclear [(Ln(tepa)(μ–OH)){sub 2}]{sup 4+} unit. Behaving as a bidentate μ–η{sup 1}, η{sup 1}–Sn{sub 2}S{sub 6} bridging ligand, the Sn{sub 2}S{sub 6} unit connects [(Ln(tepa)(μ–OH)){sub 2}]{sup 4+} units into a neutral coordination polymer [(Ln(tepa)(μ–OH)){sub 2}(μ–Sn{sub 2}S{sub 6})]{sub n} via the trans S atoms. The Ln{sup 3+} ions are in distorted monocapped square antiprismatic and bicapped trigonal prismatic environments in [(Ln(peha)(μ–SnS{sub 4}H)]{sub n} and [(Ln(tepa)(μ–OH)){sub 2}(μ–Sn{sub 2}S{sub 6})]{sub n}, respectively. The denticities of ethylene polyamine play an important role on the formation and complexation of the thiostannate in the presence of lanthanide ions. Compounds 1a–2d show well-defined absorption edges with band gaps between 2.81 and 3.15 eV. - Graphical abstract: Lanthanide coordination polymers concerning thiostannate ligands were prepared by the solvothermal methods, and μ{sub 3}–SnS{sub 4}H and μ–Sn{sub 2}S{sub 6} ligands to Ln(III) centers were obtained. - Highlights: • Lanthanide coordination polymers were prepared in polyamines with higher denticity. • The μ–η{sup 1},η{sup 2}–SnS{sub 4}H and μ–η{sup 1},η{sup 1}–Sn{sub 2}S{sub 6} ligands to Ln(III) centers were obtained. • Effect of amine on the complexation of Ln(III) with thiostannate is observed.« less

Diffusion of residual monomer in polymer resins.

PubMed Central

Piver, W T

1976-01-01

A simplified mathematical model which made use of Fick's laws of diffusion written in spherical coordinates was developed to describe the rate of diffusion of residual monomers from polymer resins. The properties of the monomer-polymer system which influenced the amount of monomer remaining in the polymer as a function of time were the diffusivity and solubility of the monomer in the polymer, and the particle size of the polymer resin. This model was used to analyze literature data on the diffusion of residual vinyl chloride monomer in polyvinyl chloride resins made by the suspension process. It was concluded that particle size of the resin was a significant parameter which should be taken advantage of in process equipment designed to remove residual monomer from PVC resins. The diffusivity of the monomer in the polymer was a function of the solubility of the monomer in the polymer. Monomer solubility can be determined from Henry's law. It was suggested that this model could be adapted to describe diffusion of monomers from any monomer-polymer system, and would be a useful approach to modeling the transport of nonreactive chemical additives from plastics. PMID:1026410

Copper coordination polymers constructed from thiazole-5-carboxylic acid: Synthesis, crystal structures, and structural transformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meundaeng, Natthaya; Rujiwatra, Apinpus; Prior, Timothy J., E-mail: t.prior@hull.ac.uk

2017-01-15

We have successfully prepared crystals of thiazole-5-carboxylic acid (5-Htza) (L) and three new thiazole-5-carboxylate-based Cu{sup 2+} coordination polymers with different dimensionality, namely, 1D [Cu{sub 2}(5-tza){sub 2}(1,10-phenanthroline){sub 2}(NO{sub 3}){sub 2}] (1), 2D [Cu(5-tza){sub 2}(MeOH){sub 2}] (2), and 3D [Cu(5-tza){sub 2}]·H{sub 2}O (3). These have been characterized by single crystal X-ray diffraction and thermogravimetry. Interestingly, the 2D network structure of 2 can directly transform into the 3D framework of 3 upon removal of methanol molecules at room temperature. 2 can also undergo structural transformation to produce the same 2D network present in the known [Cu(5-tza){sub 2}]·1.5H{sub 2}O upon heat treatment for 2more » h. This 2D network can adsorb water and convert to 3 upon exposure to air. - Highlights: • Rare examples of coordination polymers of thiazole-5-carboxylic acid were prepared. • Non-covalent interactions play a key role on the assembly of the complexes in solid state. • Structural transformation of a 2D framework to a 3D upon removal of methanol is observed.« less

Correlations in polymer blends: Simulations, perturbation theory, and coarse-grained theory

NASA Astrophysics Data System (ADS)

Chung, Jun Kyung

A thermodynamic perturbation theory of symmetric polymer blends is developed that properly accounts for the correlation in the spatial arrangement of monomers. By expanding the free energy of mixing in powers of a small parameter alpha which controls the incompatibility of two monomer species, we show that the perturbation theory has the form of the original Flory-Huggins theory, to first order in alpha. However, the lattice coordination number in the original theory is replaced by an effective coordination number. A random walk model for the effective coordination number is found to describe Monte Carlo simulation data very well. We also propose a way to estimate Flory-Huggins chi parameter by extrapolating the perturbation theory to the limit of a hypothetical system of infinitely long chains. The first order perturbation theory yields an accurate estimation of chi to first order in alpha. Going to second order, however, turns out to be more involved and an unambiguous determination of the coefficient of alpha2 term is not possible at the moment. Lastly, we test the predictions of a renormalized one-loop theory of fluctuations using two coarse-grained models of symmetric polymer blends at the critical composition. It is found that the theory accurately describes the correlation effect for relatively small values of chiN. In addition, the universality assumption of coarse-grained models is examined and we find results that are supportive of it.

An integrated logic system for time-resolved fluorescent "turn-on" detection of cysteine and histidine base on terbium (III) coordination polymer-copper (II) ensemble.

PubMed

Xue, Shi-Fan; Lu, Ling-Fei; Wang, Qi-Xian; Zhang, Shengqiang; Zhang, Min; Shi, Guoyue

2016-09-01

Cysteine (Cys) and histidine (His) both play indispensable roles in many important biological activities. An enhanced Cys level can result in Alzheimer's and cardiovascular diseases. Likewise, His plays a significant role in the growth and repair of tissues as well as in controlling the transmission of metal elements in biological bases. Therefore, it is meaningful to detect Cys and His simultaneously. In this work, a novel terbium (III) coordination polymer-Cu (II) ensemble (Tb(3+)/GMP-Cu(2+)) was proposed. Guanosine monophosphate (GMP) can self-assemble with Tb(3+) to form a supramolecular Tb(3+) coordination polymer (Tb(3+)/GMP), which can be suited as a time-resolved probe. The fluorescence of Tb(3+)/GMP would be quenched upon the addition of Cu(2+), and then the fluorescence of the as-prepared Tb(3+)/GMP-Cu(2+) ensemble would be restored again in the presence of Cys or His. By incorporating N-Ethylmaleimide and Ni(2+) as masking agents, Tb(3+)/GMP-Cu(2+) was further exploited as an integrated logic system and a specific time-resolved fluorescent "turn-on" assay for simultaneously sensing His and Cys was designed. Meanwhile it can also be used in plasma samples, showing great potential to meet the need of practical application. Copyright © 2016 Elsevier B.V. All rights reserved.

Syntheses, structures and luminescent properties of lanthanide coordination polymers assembled from imidazophenanthroline derivative and oxalate ligands

NASA Astrophysics Data System (ADS)

Zhao, Hui; Sun, Xiao-Xia; Hu, Huai-Ming; An, Ran; Yang, Meng-Lin; Xue, Ganglin

2017-01-01

Nine new lanthanide coordination polymers, namely, [Ln(Hsfpip)(ox)0.5(H2O)]n·2n(H2O) ((Ln=Eu (1), Tb (2), Dy (3), Ho (4), Er (5), Yb (6), Y(7)), [Ln(H2sfpip)(ox)(H2O)4]n·2n(H2O) (Ln=Nd (8) Sm (9)), [H2ox=oxalic acid， H3sfpip=2-(2,4-disulfophenyl)imidazo(4,5-f)(1,10)-phenanthroline] have been synthesized under hydrothermal conditions and characterized by IR spectra, elemental analysis, powder X-ray diffraction and single crystal X-ray diffraction. When sodium oxalate is added, the reactions of lanthanide ions with H3sfpip resulted in two types of structures. Compounds 1-7 are obtained at pH 5.0 and exhibit 3D tfz-d networks with ox2- anions as linkers to bridge the adjacent layers. Compounds 8-9 are obtained at pH 2.0, and display a 1D chain which is further extended to a 3D supramolecular framework through intermolecular hydrogen bonds and π-π interactions. The structural variation from compounds 1-7 to 8-9 can attribute to the pH effect on construction of lanthanide coordination polymers. Moreover, the thermal stabilities and luminescence properties of 1-9 were also investigated.

INORGANIC COORDINATION POLYMERS. IV. THE ATTEMPTED REPLACEMENT OF ACETYLACETONATE LIGANDS WITH PICOLINATE LIGANDS,

DTIC Science & Technology

HETEROCYCLIC COMPOUNDS, PHOSPHENE OXIDES, BENZENE, CHROMIUM COMPOUNDS, CHEMICAL REAC, SYNTHESIS (CHEMISTRY), CHEMICAL ANALY, SPECTRA (INFRARED), ABSORPTION, DISPLACE, POLYMERIZATION, ORGANIC NITROGEN, AROMATIC COMPOUNDS.

Building 1D lanthanide chains and non-symmetrical [Ln2] "triple-decker" clusters using salen-type ligands: magnetic cooling and relaxation phenomena.

PubMed

Canaj, Angelos B; Siczek, Milosz; Otręba, Marta; Lis, Tadeusz; Lorusso, Giulia; Evangelisti, Marco; Milios, Constantinos J

2016-11-22

A solvothermal reaction between Ln(NO 3 ) 3 ·6H 2 O (Ln: Gd, Tb and Dy), 2-hydroxy-1-naphthaldehyde, 2-OH-naphth, and ethylenediamine, en, in MeOH in the presence of a base, NEt 3 , led to the formation of the 1D coordination polymers [Ln(L)(MeO)(MeOH) 0.5 ] n ·MeOH (Ln = Gd (1·MeOH), Tb(2), Dy (3·MeOH); H 2 L = 1,1'-((1E,1'E)-(ethane-1,2-diylbis(azanylylidene))bis(methanylylidene))bis(naphthalen-2-ol), the Schiff-base ligand derived from the condensation of 2-OH-naphth and en), while a similar reaction in an excess of NaN 3 yielded 1D coordination polymers [Ln(L)(N 3 ) 0.75 (MeO) 0.25 (MeOH)] n (Ln = Gd (4), Tb (5), Dy (6)). Finally, upon replacing ethylenediamine with o-phenylenediamine, o-phen, we managed to isolate the discrete dimers [Dy 2 (L') 3 (MeOH)]·2MeOH (7·2MeOH) and [Gd 2 (L') 3 (MeOH)]·2MeOH (8·2MeOH) (H 2 L' = 1,1'-((1E,1'E)-(1,2-phenylenebis(azanylylidene))bis(methanylylidene))bis (naphthalen-2-ol), the Schiff-base ligand from the condensation of 2-OH-naphth and o-phen). Polymers 1-3 describe one-dimensional chains, containing alternating seven- and eight-coordinate Ln III metal centers, polymers 4-6 contain eight-coordinate lanthanide ions, while in both 7 and 8 the two Ln III centers are eight- and seven-coordinate, adopting square antiprismatic and "piano-stool" geometry, respectively. The magnetocaloric properties of the three Gd III analogues were determined from magnetic measurements, yielding the magnetic entropy change -ΔS m = 21.8, 23.0 and 16.0 J kg -1 K -1 at T = 3.0 K on demagnetization of 7 T to 0, for 1, 4 and 8, respectively. The study of the magnetic properties also revealed that all three Dy III analogues (3, 6 and 7) display out-of-phase signals, therefore suggesting slow magnetic relaxation, while such behaviour was not established in the Tb III analogues.

Pyrolysis of Helical Coordination Polymers for Metal-Sulfide-Based Helices with Broadband Chiroptical Activity.

PubMed

Hirai, Kenji; Yeom, Bongjun; Sada, Kazuki

2017-06-27

Fabrication of chiroptical materials with broadband response in the visible light region is vital to fully realize their potential applications. One way to achieve broadband chiroptical activity is to fabricate chiral nanostructures from materials that exhibit broadband absorption in the visible light region. However, the compounds used for chiroptical materials have predominantly been limited to materials with narrowband spectral response. Here, we synthesize Ag 2 S-based nanohelices derived from helical coordination polymers. The right- and left-handed coordination helices used as precursors are prepared from l- and d-glutathione with Ag + and a small amount of Cu 2+ . The pyrolysis of the coordination helices yields right- and left-handed helices of Cu 0.12 Ag 1.94 S/C, which exhibit chiroptical activity spanning the entire visible light region. Finite element method simulations substantiate that the broadband chiroptical activity is attributed to synergistic broadband light absorption and light scattering. Furthermore, another series of Cu 0.10 Ag 1.90 S/C nanohelices are synthesized by choosing the l- or d-Glu-Cys as starting materials. The pitch length of nanohelicies is controlled by changing the peptides, which alters their chiroptical properties. The pyrolysis of coordination helices enables one to fabricate helical Ag 2 S-based materials that enable broadband chiroptical activity but have not been explored owing to the lack of synthetic routes.

Syntheses, structures and magnetic properties of four coordination polymers based on nitrobenzene dicarboxylate and various N-donor coligands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Gui-Lian; Yin, Wei-Dong; Liu, Guang-Zhen

Four new coordination polymers ([Ni(4-Nbdc)(bpa)(H{sub 2}O)]){sub n} (1), ([Co(4-Nbdc)(bpp) (H{sub 2}O)]){sub n} (2), ([Ni(4-Nbdc)(bpp)(H{sub 2}O)]·H{sub 2}O){sub n} (3), and ([Mn{sub 2}(3-Nbdc){sub 2}(bib){sub 3}]·2H{sub 2}O){sub n} (4) (4-Nbdc=4-nitrobenzene-1,2-dicarboxylate, 3-Nbdc=3-nitrobenzene-1,2-dicarboxylate, bpa=1,2-bi(4-pyridyl)ethane, bpp=1,3-bis(4-pyridyl)propane, and bib=1,4-bis(1-imidazoly)benzene), were synthesized by hydrothermal reactions, and characterized by single-crystal X-ray diffractions, elemental analysis, FT-IR, PXRD, TGA and magnetic analysis. Complexes 1 and 2 display quasi-trapezoidal chain and brick-wall layer, and both of them contain metal–carboxylate binuclear units. Complexes 3 and 4 exhibit three-dimensional frameworks with the (6{sup 6}) dia topology and (4{sup 4}.6{sup 10}.8)(4{sup 4}.6{sup 2}) fsc topology, and both of them contain metal–carboxylate chains. The carboxyl groupsmore » with syn-anti coordination mode mediate effectively the weak ferromagnetic coupling interaction within Ni(II)–carboxylate binuclear in 1 (J=1.27 cm{sup −1}) and Ni(II)–carboxylate chain in 3 (J=1.44 cm{sup −1}), respectively, and the carboxyl groups with anti-anti coordination mode leads to the classic antiferromagnetic coupling interaction within Mn(II)–carboxylate chain in 4 (J=−0.77 cm{sup −1}). - Highlights: • Four novel coordination polymers were hydrothermally synthesized. • 1 is 1D quasi-trapezoidal chain and 2 is brick-wall layer both with dinuclear units. • 3 and 4 show 3D frameworks both with 1D metal–carboxylate chains. • 1 and 3 exhibit ferromagnetic coupling, while 4 shows antiferromagnetic coupling.« less

Box-like gel capsules from heterostructures based on a core-shell MOF as a template of crystal crosslinking.

PubMed

Ishiwata, Takumi; Michibata, Ayano; Kokado, Kenta; Ferlay, Sylvie; Hosseini, Mir Wais; Sada, Kazuki

2018-02-06

New polymer capsules (PCs) were obtained using a crystal crosslinking (CC) method on core-shell MOF crystals. The latter are based on the epitaxial growth of two isostructural coordination polymers which are then selectively crosslinked. Decomposition of the non-reticulated phase leads to new PCs, possessing a well-defined hollow cubic shape reflecting the heterostructure of the template.

Making Ceramic/Polymer Parts By Extrusion Stereolithography

NASA Technical Reports Server (NTRS)

Stuffle, Kevin; Mulligan, A.; Creegan, P.; Boulton, J. M.; Lombardi, J. L.; Calvert, P. D.

1996-01-01

Extrusion stereolithography developmental method of computer-controlled manufacturing of objects out of ceramic/polymer composite materials. Computer-aided design/computer-aided manufacturing (CAD/CAM) software used to create image of desired part and translate image into motion commands for combination of mechanisms moving resin dispenser. Extrusion performed in coordination with motion of dispenser so buildup of extruded material takes on size and shape of desired part. Part thermally cured after deposition.

Mesoporous imine-based organic polymer: catalyst-free synthesis in water and application in CO2 conversion.

PubMed

Yu, Xiaoxiao; Yang, Zhenzhen; Guo, Shien; Liu, Zhenghui; Zhang, Hongye; Yu, Bo; Zhao, Yanfei; Liu, Zhimin

2018-06-22

A mesoporous imine-functionalized organic polymer (Imine-POP) was prepared based on the reaction of an aryl ammonium salt with an aromatic aldehyde in water without any catalyst and template. The Pd coordinated Imine-POP exhibited high catalytic activity for the N-formylation of amines with CO2/H2 at 100 °C, affording a series of formamides in high yields.

Efficient white-light-emitting diodes based on poly(N-vinylcarbazole) doped with blue fluorescent and orange phosphorescent materials

NASA Astrophysics Data System (ADS)

Shih, Ping-I.; Shu, Ching-Fong; Tung, Yung-Liang; Chi, Yun

2006-06-01

We have fabricated polymer white-light-emitting devices possessing a single emitting layer containing a hole-transporting host polymer, poly(N-vinylcarbazole), and an electron-transporting auxiliary, 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole, doped with a blue-light-emitting amino-substituted distyrylarylene fluorescent dye and an orange-light-emitting osmium phosphor. The doubly doped device exhibited an intense white emission having Commission Internationale de l'Eclairage coordinates of (0.33, 0.34), a high external quantum efficiency of 6.12% (13.2cd/A), and a maximum brightness of 11306cd/m2. The color coordinates remained unchanged over a range of operating voltages, even at luminance as high as 1×104cd/m2.

Syntheses, crystal structures and properties of series of 4d-4f ln(III)-Ag(I) heterometallic coordination polymers

NASA Astrophysics Data System (ADS)

Ran, Xing-Rui; Wang, Ning; Xie, Wei-Ping; Xiong, Yan-Ju; Cheng, Qian; Long, Yi; Yue, Shan-Tang; Liu, Ying-Liang

2015-05-01

By control of the experimental parameters such as ligands, pH value and reacting temperature, series of three-dimensional (3D) 4d-4f Ln(III)-Ag(I) porous coordination polymers (PCPs) with interesting chain-layer construction, namely, {[LnIIIAgI(na)(ina)(ox)]·2(H2O)}n [Ln=Sm(1), Eu(2), Gd(3), Tb(4), Dy(5), Ho(6), Y(7), Yb(8)], have been successfully synthesized under hydrothermal conditions and structurally characterized. All the complexes are characterized by elemental analyses, FT-IR spectroscopy, Powder X-ray diffraction (PXRD) and thermogravimetric analyses (TGA). Furthermore, the luminescence properties of compounds 2 and 4 and the magsnetic properties of complexes 3 and 5 were also investigated in detail.

Interpenetrating and non-interpenetrating 3-dimensional coordination polymer frameworks from multiple building blocks

NASA Astrophysics Data System (ADS)

Bradshaw, Darren; Rosseinsky, Matthew J.

2005-12-01

Reaction of Co(NO3)2ṡ6H2O with the multidentate ligands benzene-1,3,5-tricarboxylate (btc) and the flexible bipyridyl ligand 1,2-bis(4-pyridyl)ethane (bpe) affords the 3-dimensional coordination polymers [Co3(btc)2(bpe)3(eg)2]ṡ(guests) 1, where eg = ethylene glycol, and [Co2(Hbtc)2(bpe)2]ṡ(bpe) 2. Both phases are comprised of infinite metal-carboxylate dimer chains, linked into 2-dimensional sheets by the bpe ligands. These sheets are further linked to adjacent sheets through covalent interactions, 1, or through hydrogen-bonding interactions, 2, to yield the 3-dimensional structures. Phase 1 exhibits solvent filled 1-dimensional pores, whereas 2 is triply-interpenetrated to form a dense solid array.

Lanthanide-based coordination polymers assembled by a flexible multidentate linker: design, structure, photophysical properties, and dynamic solid-state behavior.

PubMed

Marchal, Claire; Filinchuk, Yaroslav; Chen, Xiao-Yan; Imbert, Daniel; Mazzanti, Marinella

2009-01-01

Four picolinate building blocks were implemented into the multidentate linker N,N',N'-tetrakis[(6-carboxypyridin-2-yl)methyl]butylenediamine (H(4)tpabn) with a linear flexible spacer to promote the assembly of lanthanide-based 1D coordination polymers. The role of the linker in directing the geometry of the final assembly is evidenced by the different results obtained in the presence of Htpabn(3-) and tpabn(4-) ions. The tpabn(4-) ion leads to the desired 1D polymer {[Nd(tpabn)]H(3)O x 6 H(2)O}(infinity) (12). The Htpabn(3-) ion leads to the assembly of Tb(III) and Er(III) ions into 1D zigzag chains of the general formula {[M(Htpabn)] x xH(2)O}(infinity) (M = Tb, x = 14 (1); M = Tb, x = 8 (11); M = Er, x = 14 (2); M = Er, x = 5.5 (4)), a 2D network is formed by the Eu(III) ion (i.e., {[Eu(Htpabn)] x 10 H(2)O}(infinity) (7)), and both supramolecular isomers (1D and 2D) are obtained by the Tb(III) ion. The high flexibility of the polymeric chains results in a dynamic behavior with a solvent-induced reversible structural transition. The Tb(III)- and Eu(III)-containing polymers display high-luminescence quantum yields (38 and 18%, respectively). A sizeable near-IR luminescence emission is observed for the Er(III)- and Nd(III)-containing polymers when lattice water molecules are removed.

Assembly of three new POM-based Ag(I) coordination polymers with antibacterial and photocatalytic properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, Xin-Xin; Luo, Yu-Hui; Lu, Chen

Three new silver coordination polymers, namely, {Ag_3(bpy)_6[PW_1_2O_4_0]} (1), {Ag_5(H_2biim)_2(Hbiim-NO_2)_2[PW_1_2O_4_0]} (2), {Ag_7(pytz)_4[PW_1_2O_4_0]} (3) (bpy=2,2′-bipyridine, H{sub 2}biim=2,2′-biimidazole, pytz=4-(1H-tetrazol-5-yl)pyridine), have been synthesized under hydrothermal condition. Compound 1 shows a 3D supramolecular framework based on 0D moieties. Compound 2 exhibits an attractive 2D biologic screw axis. Compound 3 displays a 3D structure, which consists of Ag(I)···π interactions, π···π stacking and weak Ag···Ag interactions. It is noteworthy that nitration happens to compound 2 during the hydrothermal condition, which is quite rare. Through contrasting the antibacterial activities of gram negative and gram positive bacteria, we find compounds 1–3 have better antibacterial property in gram negative bacteriamore » than gram positive bacteria. In addition, compounds 1–3 also exhibit efficiency of photocatalytic decomposition of organic dyes. Those compounds may be used as potential multifunctional materials in wastewater treatment, because they not only can kill bacteria but also degrade organic pollutants. - Highlights: • Three new silver coordination polymers have been synthesized under hydrothermal condition. • Due to different coordination modes of rigid N-donor ligands, structures of the title compounds vary from 0D to 3D frameworks. • It is noteworthy that nitration happens to compound 2 during the hydrothermal condition, which is quite rare. • In addition, these compounds exhibit efficiency of photocatalytic decomposition of dyes and antibacterial activities.« less

Coordination in Large Scale Software Development

DTIC Science & Technology

1990-01-01

toward achieving common and explicitly recognized goals" (Blau and Scott, 1962) and "the integration or linking together of different parts of an...require a strong degree of integration of its components. Much software is built of thousands of modules that must mesh with each other perfectly for the...coordination between subgroups producing software modules could lead to failure in integrating the modules themselves. Informal communication. Both

Conformal Robotic Stereolithography

PubMed Central

Stevens, Adam G.; Oliver, C. Ryan; Kirchmeyer, Matthieu; Wu, Jieyuan; Chin, Lillian; Polsen, Erik S.; Archer, Chad; Boyle, Casey; Garber, Jenna

2016-01-01

Abstract Additive manufacturing by layerwise photopolymerization, commonly called stereolithography (SLA), is attractive due to its high resolution and diversity of materials chemistry. However, traditional SLA methods are restricted to planar substrates and planar layers that are perpendicular to a single-axis build direction. Here, we present a robotic system that is capable of maskless layerwise photopolymerization on curved surfaces, enabling production of large-area conformal patterns and the construction of conformal freeform objects. The system comprises an industrial six-axis robot and a custom-built maskless projector end effector. Use of the system involves creating a mesh representation of the freeform substrate, generation of a triangulated toolpath with curved layers that represents the target object to be printed, precision mounting of the substrate in the robot workspace, and robotic photopatterning of the target object by coordinated motion of the robot and substrate. We demonstrate printing of conformal photopatterns on spheres of various sizes, and construction of miniature three-dimensional objects on spheres without requiring support features. Improvement of the motion accuracy and development of freeform toolpaths would enable construction of polymer objects that surpass the size and support structure constraints imparted by traditional SLA systems. PMID:29577062

Effects of rotational symmetry breaking in polymer-coated nanopores

NASA Astrophysics Data System (ADS)

Osmanović, D.; Kerr-Winter, M.; Eccleston, R. C.; Hoogenboom, B. W.; Ford, I. J.

2015-01-01

The statistical theory of polymers tethered around the inner surface of a cylindrical channel has traditionally employed the assumption that the equilibrium density of the polymers is independent of the azimuthal coordinate. However, simulations have shown that this rotational symmetry can be broken when there are attractive interactions between the polymers. We investigate the phases that emerge in these circumstances, and we quantify the effect of the symmetry assumption on the phase behavior of the system. In the absence of this assumption, one can observe large differences in the equilibrium densities between the rotationally symmetric case and the non-rotationally symmetric case. A simple analytical model is developed that illustrates the driving thermodynamic forces responsible for this symmetry breaking. Our results have implications for the current understanding of the behavior of polymers in cylindrical nanopores.

Effects of rotational symmetry breaking in polymer-coated nanopores

DOE Office of Scientific and Technical Information (OSTI.GOV)

Osmanović, D.; Hoogenboom, B. W.; Ford, I. J.

2015-01-21

The statistical theory of polymers tethered around the inner surface of a cylindrical channel has traditionally employed the assumption that the equilibrium density of the polymers is independent of the azimuthal coordinate. However, simulations have shown that this rotational symmetry can be broken when there are attractive interactions between the polymers. We investigate the phases that emerge in these circumstances, and we quantify the effect of the symmetry assumption on the phase behavior of the system. In the absence of this assumption, one can observe large differences in the equilibrium densities between the rotationally symmetric case and the non-rotationally symmetricmore » case. A simple analytical model is developed that illustrates the driving thermodynamic forces responsible for this symmetry breaking. Our results have implications for the current understanding of the behavior of polymers in cylindrical nanopores.« less

Probing polymer crystallization at processing-relevant cooling rates with synchrotron radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cavallo, Dario, E-mail: Dario.cavallo@unige.it; Portale, Giuseppe; Androsch, René

2015-12-17

Processing of polymeric materials to produce any kind of goods, from films to complex objects, involves application of flow fields on the polymer melt, accompanied or followed by its rapid cooling. Typically, polymers solidify at cooling rates which span over a wide range, from a few to hundreds of °C/s. A novel method to probe polymer crystallization at processing-relevant cooling rates is proposed. Using a custom-built quenching device, thin polymer films are ballistically cooled from the melt at rates between approximately 10 and 200 °C/s. Thanks to highly brilliant synchrotron radiation and to state-of-the-art X-ray detectors, the crystallization process ismore » followed in real-time, recording about 20 wide angle X-ray diffraction patterns per second while monitoring the instantaneous sample temperature. The method is applied to a series of industrially relevant polymers, such as isotactic polypropylene, its copolymers and virgin and nucleated polyamide-6. Their crystallization behaviour during rapid cooling is discussed, with particular attention to the occurrence of polymorphism, which deeply impact material’s properties.« less

Metal coordination polymer derived mesoporous Co3O4 nanorods with uniform TiO2 coating as advanced anodes for lithium ion batteries.

PubMed

Geng, Hongbo; Ang, Huixiang; Ding, Xianguang; Tan, Huiteng; Guo, Guile; Qu, Genlong; Yang, Yonggang; Zheng, Junwei; Yan, Qingyu; Gu, Hongwei

2016-02-07

In this work, a one-dimensional Co3O4@TiO2 core-shell electrode material with superior electrochemical performance is fabricated by a convenient and controllable route. The approach involves two main steps: the homogeneous deposition of polydopamine and TiO2 layers in sequence on the cobalt coordination polymer and the thermal decomposition of the polymer matrix. The as-prepared electrode material can achieve excellent electrochemical properties and stability as an anode material for lithium ion batteries, such as a high specific capacity of 1279 mA h g(-1), good cycling stability (around 803 mA h g(-1) at a current density of 200 mA g(-1) after 100 cycles), and stable rate performance (around 520 mA h g(-1) at a current density of 1000 mA g(-1)). This dramatic electrochemical performance is mainly attributed to the excellent structural characteristics, which could improve the electrical conductivity and lithium ion mobility, as well as electrolyte permeability and architectural stability during cycling.

Coordination Polymers Containing 1,3-Phenylenebis-((1H-1,2,4-triazol-1-yl)methanone) Ligand: Synthesis and ε-Caprolactone Polymerization Behavior.

PubMed

Bello-Vieda, Nestor J; Murcia, Ricardo A; Muñoz-Castro, Alvaro; Macías, Mario A; Hurtado, John J

2017-11-10

The reaction of isophthaloyl dichloride with 1 H -1,2,4-triazole afforded the new ligand 1,3-phenylenebis(1,2,4-triazole-1-yl)methanone ( 1 ). A series of Co(II), Cu(II), Zn(II) and Ni(II) complexes were synthesized using 1 and then characterized by melting point analysis, elemental analysis, theoretical calculations, thermogravimetric analysis, X-ray powder diffraction, nuclear magnetic resonance, infrared and Raman spectroscopy. Experimental and computational studies predict the formation of coordination polymers (CPs). The cobalt and copper CPs and zinc(II) complex were found to be good initiators for the ring-opening polymerization of ε-caprolactone (CL) under solvent-free conditions. ¹H-NMR analysis showed that the obtained polymers of CL were mainly linear and had terminal hydroxymethylene groups. Differential scanning calorimetry showed that the obtained polycaprolactones had high crystallinity, and TGA showed that they had decomposition temperatures above 400 °C. These results provide insight and guidance for the design of metal complexes with potential applications in the polymerization of CL.

Towards Acid-Tolerated Ethanol Dehydration: Chitosan-Based Mixed Matrix Membranes Containing Cyano-Bridged Coordination Polymer Nanoparticles.

PubMed

Wu, C-W; Kang, Chao-Hsiang; Lin, Yi-Feng; Tung, Kuo-Lun; Deng, Yu-Heng; Ahamad, Tansir; Alshehri, Saad M; Suzuki, Norihiro; Yamauchi, Yusuke

2016-04-01

Prussian blue (PB) nanoparticles, one of many cyano-bridged coordination polymers, are successfully incorporated into chitosan (CS) polymer to prepare PB/CS mixed matrix membranes (MMMs). The PB nanoparticles are uniformly distributed in the MMMs without the collapse of the original PB structure. As-prepared PB/CS MMMs are used for ethanol dehydration at 25 °C in the pervaporation process. The effect of loading PB in CS matrix on pervaporation performance is carefully investigated. The PB/CS membrane with 30 wt% PB loading shows the best performance with a permeate flux of 614 g. m-2 . h-1 and a separation factor of 1472. The pervaporation using our PB/CS membranes exhibits outstanding performance in comparison with the previously reported CS-based membranes and MMMs. Furthermore, the addition of PB allows PB/CS MMMs to be tolerant of acidic environment. The present work demonstrates good pervaporation performance of PB/CS MMMs for the separation of an ethanol/water (90:10 in wt%) solution. Our new system provides an opportunity for dehydration of bioethanol in the future.

Coordination polymer structure and revisited hydrogen evolution catalytic mechanism for amorphous molybdenum sulfide

PubMed Central

Tran, Phong D.; Tran, Thu V.; Orio, Maylis; Torelli, Stephane; Truong, Quang Duc; Nayuki, Keiichiro; Sasaki, Yoshikazu; Chiam, Sing Yang; Yi, Ren; Honma, Itaru; Barber, James; Artero, Vincent

2017-01-01

Molybdenum sulfides are very attractive noble-metal free electrocatalysts for the hydrogen evolution reaction (HER) from water. Atomic structure and identity of the catalytically active sites have been well established for crystalline molybdenum disulfide (c-MoS2) but not for amorphous molybdenum sulfide (a-MoSx) which displays significantly higher HER activity compared to its crystalline counterpart. Here we show that HER–active a-MoSx, prepared either as nanoparticles or as films, is a molecular–based coordination polymer consisting of discrete [Mo3S13]2– building blocks. Of the three terminal disulfide (S22–) ligands within these clusters, two are shared to form the polymer chain. The third one remains free and generates molybdenum hydride moieties as the active site under H2 evolution conditions. Such a molecular structure therefore provides a basis for revisiting the mechanism of a-MoSx catalytic activity, as well as explaining some of its special properties such as reductive activation and corrosion. Our findings open up new avenues for the rational optimisation of this HER electrocatalyst as an alternative to platinum. PMID:26974410

Supramolecular architectures in Co(II) and Cu(II) complexes with thiophene-2-carboxylate and 2-amino-4,6-dimethoxypyrimidine ligands.

PubMed

Karthikeyan, Ammasai; Thomas Muthiah, Packianathan; Perdih, Franc

2016-05-01

The coordination chemistry of mixed-ligand complexes continues to be an active area of research since these compounds have a wide range of applications. Many coordination polymers and metal-organic framworks are emerging as novel functional materials. Aminopyrimidine and its derivatives are flexible ligands with versatile binding and coordination modes which have been proven to be useful in the construction of organic-inorganic hybrid materials and coordination polymers. Thiophenecarboxylic acid, its derivatives and their complexes exhibit pharmacological properties. Cobalt(II) and copper(II) complexes of thiophenecarboxylate have many biological applications, for example, as antifungal and antitumor agents. Two new cobalt(II) and copper(II) complexes incorporating thiophene-2-carboxylate (2-TPC) and 2-amino-4,6-dimethoxypyrimidine (OMP) ligands have been synthesized and characterized by X-ray diffraction studies, namely (2-amino-4,6-dimethoxypyrimidine-κN)aquachlorido(thiophene-2-carboxylato-κO)cobalt(II) monohydrate, [Co(C5H3O2S)Cl(C6H9N3O2)(H2O)]·H2O, (I), and catena-poly[copper(II)-tetrakis(μ-thiophene-2-carboxylato-κ(2)O:O')-copper(II)-(μ-2-amino-4,6-dimethoxypyrimidine-κ(2)N(1):N(3))], [Cu2(C5H3O2S)4(C6H9N3O2)]n, (II). In (I), the Co(II) ion has a distorted tetrahedral coordination environment involving one O atom from a monodentate 2-TPC ligand, one N atom from an OMP ligand, one chloride ligand and one O atom of a water molecule. An additional water molecule is present in the asymmetric unit. The amino group of the coordinated OMP molecule and the coordinated carboxylate O atom of the 2-TPC ligand form an interligand N-H...O hydrogen bond, generating an S(6) ring motif. The pyrimidine molecules also form a base pair [R2(2)(8) motif] via a pair of N-H...N hydrogen bonds. These interactions, together with O-H...O and O-H...Cl hydrogen bonds and π-π stacking interactions, generate a three-dimensional supramolecular architecture. The one-dimensional coordination polymer (II) contains the classical paddle-wheel [Cu2(CH3COO)4(H2O)2] unit, where each carboxylate group of four 2-TPC ligands bridges two square-pyramidally coordinated Cu(II) ions and the apically coordinated OMP ligands bridge the dinuclear copper units. Each dinuclear copper unit has a crystallographic inversion centre, whereas the bridging OMP ligand has crystallographic twofold symmetry. The one-dimensional polymeric chains self-assemble via N-H...O, π-π and C-H...π interactions, generating a three-dimensional supramolecular architecture.

Syntheses, structures and photoelectric properties of a series of Cd(II)/Zn(II) coordination polymers and coordination supramolecules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin Jing; Han Xiao; Meng Qin

2013-01-15

Five Cd(II)/Zn(II) complexes [Cd(1,2-bdc)(pz){sub 2}(H{sub 2}O)]{sub n} (1), [Cd1Cd2(btec)(H{sub 2}O){sub 6}]{sub n} (2), [Cd(3,4-pdc) (H{sub 2}O)]{sub n} (3), [Zn(2,5-pdc)(H{sub 2}O){sub 4}]{center_dot}2H{sub 2}O (4) and {l_brace} [Zn(2,5-pdc)(H{sub 2}O){sub 2}]{center_dot}H{sub 2}O{r_brace} {sub n} (5) (H{sub 2}bdc=1,2-benzenedicarboxylic acid, pz=pyrazole, H{sub 4}btec=1,2,4,5-benzenetetracarboxylic acid, H{sub 2}pdc=pyridine-dicarboxylic acid) were hydrothermally synthesized and characterized by single-crystal X-ray diffraction, surface photovoltage spectroscopy, XRD, TG analysis, IR and UV-vis spectra and elemental analysis. Structural analyses show that complexes 1-3 are 1D, 2D and 3D Cd(II) coordination polymers, respectively. Complex 4 is a mononuclear Zn(II) complex. Complex 5 is a 3D Zn(II) coordination polymer. The surface photoelectric properties of complexesmore » were investigated by SPS. The results indicate that all complexes exhibit photoelectric responses in the range of 300-600 nm, which reveals that they all possess certain photoelectric conversion properties. By the comparative analyses, it can be found that the species and coordination micro-environment of central metal ion, the species and property of ligands affect the intensity and scope of photoelectric response. - Graphical abstract: Five Cd(II)/Zn(II) complexes have been hydrothermally synthesized and characterized. The photoelectric properties were studied with SPS. The species and coordination micro-environment of central metal ion, the species and property of ligands all affect the photoelectric responses. Highlights: Black-Right-Pointing-Pointer Five Cd/Zn complexes have been synthesized and characterized. Black-Right-Pointing-Pointer The SPS results indicate they possess obvious photoelectric conversion property. Black-Right-Pointing-Pointer The species and coordination environment of central metal ion affect SPS. Black-Right-Pointing-Pointer The species and property of ligands affect SPS. Black-Right-Pointing-Pointer By the energy-band theory and the crystal filed theory, the SPS are analyzed and assigned.« less

Dynamical formation of spatially localized arrays of aligned nanowires in plastic films with magnetic anisotropy.

PubMed

Fragouli, Despina; Buonsanti, Raffaella; Bertoni, Giovanni; Sangregorio, Claudio; Innocenti, Claudia; Falqui, Andrea; Gatteschi, Dante; Cozzoli, Pantaleo Davide; Athanassiou, Athanassia; Cingolani, Roberto

2010-04-27

We present a simple technique for magnetic-field-induced formation, assembling, and positioning of magnetic nanowires in a polymer film. Starting from a polymer/iron oxide nanoparticle casted solution that is allowed to dry along with the application of a weak magnetic field, nanocomposite films incorporating aligned nanocrystal-built nanowire arrays are obtained. The control of the dimensions of the nanowires and of their localization across the polymer matrix is achieved by varying the duration of the applied magnetic field, in combination with the evaporation dynamics. These multifunctional anisotropic free-standing nanocomposite films, which demonstrate high magnetic anisotropy, can be used in a wide field of technological applications, ranging from sensors to microfluidics and magnetic devices.

Fabrication of Polyvinylpyrrolidone Micro-/Nanostructures Utilizing Microcontact Printing

ERIC Educational Resources Information Center

Sanders, Wesley C.

2015-01-01

This paper describes a laboratory exercise that provides students enrolled in introductory nanotechnology courses with an opportunity to synthesize polymer structures with micro- and nanoscale dimensions. Polyvinylpyrrolidone (PVP) films deposited on corrugated PDMS stamps using student-built spin coaters were transferred to clean, dry substrates…

New 3-D coordination polymers based on semi-rigid V-shape tetracarboxylates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Jing-Jing; Xu, Wei; Wang, Yan-Ning

Under the hydrothermal conditions, the reactions of transition-metal salts, tetracarboxylic acids and N,N′-donor ligands yielded three new coordination polymers as [Cu{sub 4}(fph){sub 2}(bpe){sub 3}(H{sub 2}O){sub 2}]·2H{sub 2}O (fph=4,4′-(hexafluoroisopropylidene)diphthalate, bpe=1,2-bis(pyridyl)ethylene) 1, [Co{sub 2}(fph)(bpa){sub 2}(H{sub 2}O){sub 2}]·3H{sub 2}O (bpa=1,2-bis(pyridyl)ethylane) 2, and [Ni(H{sub 2}O)(H{sub 2}oph)(bpa)] (oph=4,4′-oxydiphthalate) 3. X-ray single-crystal diffraction analysis revealed that the title three compounds all possess the three-dimensional (3-D) network structures. For compound 1, the fph molecules first link the Cu{sup 2+} ions into a two-dimensional (2-D) wave-like layer with a (4,4) topology. The bpe molecules act as the second linkers, extending the 2-D layers into a 3-D network. Formore » compound 2, the fph molecules still serve as the first connectors, linking the Co{sup 2+} ions into a one-dimensional (1-D) tube-like chain. Then the bpa molecules propagate the chains into a 3-D (4,4,4)-connected network. In the formation of the 3-D network of compound 3, the oph molecule does not play a role. The bpa molecules as well as the water molecules act as a mixed bridge. Only a kind of 4-connected metal node is observed in compound 3. The magnetic properties of compounds 1–3 were investigated and all exhibit the predominant antiferromegnetic magnetic behaviors. - Graphical abstract: Structures of three semi-rigid V-shape tetracarboxylate-based coordination polymers were reported, and their magnetic properties were investigated. - Highlights: • Structures of three tetracarboxylate-based coordination polymers were reported. • Role of organic bases in metal–tetracarboxylate compounds was discussed. • Characters of V-shape and semi-rigidity for tetracarboxylate play a key role in crystal growth. • Their magnetic properties were investigated.« less

Gas adsorption/separation properties of metal directed self-assembly of two coordination polymers with 5-nitroisophthalate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arıcı, Mürsel; Yeşilel, Okan Zafer, E-mail: yesilel@ogu.edu.tr; Keskin, Seda

2014-02-15

Two new coordination polymers, namely, [Co(µ-nip)(µ-bpe)]{sub n} (1) and [Zn(µ-nip)(µ-bpe)]{sub n} (2) (nip: 5-nitroisophthalate, bpe: 1,2-bis(4-pyridyl)ethane) were hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction, IR spectroscopy, elemental analysis and thermal analysis. Moreover, atomically detailed simulation studies of complex 2 for CO{sub 2}/CH{sub 4} adsorption and separation were performed. Complex 1 consists of two dimensional (2D) (4,4) grid networks with the point symbol of 4{sup 4}.6{sup 2}. Complex 2 exhibits a 3-fold interpenetrating 3D framework with 6{sup 5}.8-dmp topology. Thermal properties of the complexes showed that both complexes were stable over 320 °C. Simulation studies demonstrated that complexmore » 2 can separate CO{sub 2} from CH{sub 4} at low pressures at 273 K. - Graphical abstract: In this study, two new coordination polymers, namely, [Co(µ-nip)(µ-bpe)]{sub n} (1) and [Zn(µ-nip)(µ-bpe)]{sub n} (2) (nip: 5-nitroisophthalate, bpe: 1,2-bis(4-pyridyl)ethane) were hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction, IR spectroscopy, elemental analysis and thermal analysis. Moreover, atomically detailed simulation studies of complex 2 for CO{sub 2}/CH{sub 4} adsorption and separation were performed. Complex 1 consists of two dimensional (2D) (4,4) grid networks with the point symbol of 4{sup 4}.6{sup 2}. Complex 2 exhibits a 3-fold interpenetrating 3D framework with 6{sup 5}.8-dmp topology. Simulation studies demonstrated that complex 2 can separate CO{sub 2} from CH{sub 4} at low pressures at 273 K. Display Omitted - Highlights: • Two new coordination polymers with 5-nitroisophthalate and 1,2-bis(4-pyridyl)ethane. • Atomically detailed simulation studies of the complexes. • Complex 2 can be proposed as molecular sieve to separate CO{sub 2} from CH{sub 4} at low pressures.« less

N-donor co-ligands driven two new Co(II)- coordination polymers with bi- and trinuclear units: Crystal structures, and magnetic properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Zhi-Hang; Han, Min-Le; Wu, Ya-Pan

2016-10-15

Two new Co(II) coordination polymers(CPs), namely [Co{sub 2}(bpe){sub 2}(Hbppc)]{sub n} (1) and [Co{sub 3}(μ{sub 3}-OH)(bppc)(bpm)(H{sub 2}O)]·3H{sub 2}O (2) (H{sub 5}bppc=biphenyl-2,4,6,3′,5′-pentacarboxylic acid, bpe=1,2-bis(4-pyridyl)ethene, bpm=bis(4-pyridyl)amine), have been obtained and characterized by elemental analysis, single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), IR spectra and thermogravimetric analysis (TGA). 1 shows a binodal (4,6)-connected fsc net with a (4{sup 4}·6{sup 10}·8)(4{sup 4}·6{sup 2}) topology, while 2 shows a binodal (5,7)-connected 3D network based on trinuclear [Co{sub 3}(μ{sub 3}-OH)]{sup 5+} units with unusual (3.4{sup 6}.5{sup 2}.6)(3{sup 2}.4{sup 6}.5{sup 7}.6{sup 5}.7) topology. Variable-temperature magnetic susceptibility measurements reveals that complex 1 shows ferromagnetic interactions between the adjacent Co(II)more » ions, whereas 2 is a antiferromagnetic system. - Graphical abstract: Two new Co(II) coordination polymers with bi- and trinuclear units have been obtained. 1 shows a binodal (4,6)-connected fsc net with a (4{sup 4}·6{sup 10}·8)(4{sup 4}·6{sup 2}) topology and antiferromagnetic interactions between the adjacent Co(II) ions, while 2 is a binodal (5,7)-connected 3D network with unusual (3.4{sup 6}.5{sup 2}.6)(3{sup 2}.4{sup 6}.5{sup 7}.6{sup 5}.7) topology and a ferromagnetic system. - Highlights: • Two Co(II) coordination polymers with different multimetallic clusters as building units. • A (4,6)-connected fsc net and a (5,7)-connected 3D network. • A antiferromagnetic coupling for 1 and A ferromagnetic coupling for 2.« less

(1-Butyl-4-methyl-pyridinium)[Cu(SCN)2]: a coordination polymer and ionic liquid.

PubMed

Spielberg, Eike T; Edengeiser, Eugen; Mallick, Bert; Havenith, Martina; Mudring, Anja-Verena

2014-04-25

The compound (C4C1py)[Cu(SCN)2], (C4C1py = 1-Butyl-4-methyl-pyridinium), which can be obtained from CuSCN and the ionic liquid (C4C1py)(SCN), turns out to be a new organic-inorganic hybrid material as it qualifies both, as a coordination polymer and an ionic liquid. It features linked [Cu(SCN)2](-) units, in which the thiocyanates bridge the copper ions in a μ1,3-fashion. The resulting one-dimensional chains run along the a axis, separated by the C4C1py counterions. Powder X-ray diffraction not only confirms the single-crystal X-ray structure solution but proves the reformation of the coordination polymer from an isotropic melt. However, the materials shows a complex thermal behavior often encountered for ionic liquids such as a strong tendency to form a supercooled melt. At a relatively high cooling rate, glass formation is observed. When heating this melt in differential scanning calorimetry (DSC) and temperature-dependent polarizing optical microscopy (POM), investigations reveal the existence of a less thermodynamically stable crystalline polymorph. Raman measurements conducted at 10 and 100 °C point towards the formation of polyanionic chain fragments in the melt. Solid-state UV/Vis spectroscopy shows a broad absorption band around 18,870 cm(-1) (530 nm) and another strong one below 20,000 cm(-1) (<500 nm). The latter is attributed to the d(Cu(I))→π*(SCN)-MLCT (metal-to-ligand charge transfer) transition within the coordination polymer yielding an energy gap of 2.4 eV. At room temperature and upon irradiation with UV light, the material shows a weak fluorescence band at 15,870 cm(-1) (630 nm) with a quantum efficiency of 0.90(2) % and a lifetime of 131(2) ns. Upon lowering the temperature, the luminescence intensity strongly increases. Simultaneously, the band around 450 nm in the excitation spectrum decreases. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Covalent-supramolecular hybrid polymers as muscle-inspired anisotropic actuators.

PubMed

Chin, Stacey M; Synatschke, Christopher V; Liu, Shuangping; Nap, Rikkert J; Sather, Nicholas A; Wang, Qifeng; Álvarez, Zaida; Edelbrock, Alexandra N; Fyrner, Timmy; Palmer, Liam C; Szleifer, Igal; Olvera de la Cruz, Monica; Stupp, Samuel I

2018-06-19

Skeletal muscle provides inspiration on how to achieve reversible, macroscopic, anisotropic motion in soft materials. Here we report on the bottom-up design of macroscopic tubes that exhibit anisotropic actuation driven by a thermal stimulus. The tube is built from a hydrogel in which extremely long supramolecular nanofibers are aligned using weak shear forces, followed by radial growth of thermoresponsive polymers from their surfaces. The hierarchically ordered tube exhibits reversible anisotropic actuation with changes in temperature, with much greater contraction perpendicular to the direction of nanofiber alignment. We identify two critical factors for the anisotropic actuation, macroscopic alignment of the supramolecular scaffold and its covalent bonding to polymer chains. Using finite element analysis and molecular calculations, we conclude polymer chain confinement and mechanical reinforcement by rigid supramolecular nanofibers are responsible for the anisotropic actuation. The work reported suggests strategies to create soft active matter with molecularly encoded capacity to perform complex tasks.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arya, Anil; Sharma, Sweety; Sharma, A. L., E-mail: alsharmaiitkgp@gmail.com

Blend polymer electrolytes are prepared for salt concentration (Ö/Li = 4) with the constant ratio (0.5 gm) of PEO and PAN using solution casting technique. The prepared free standing solid polymeric film is characterized by Field Emission Scanning Electron Microscopy (FESEM) which confirms the homogeneous distribution of dissociated salt in blend polymer matrix. After addition of salt the ionic conductivity value is found to be of the order of 7.13 × 10{sup −5} Scm{sup −1} which is three orders higher when compared with pure blend polymer films. The microscopic interaction among the polymer-ion, ion-ion has been confirmed by the Fouriermore » Transform Infrared (FTIR) Spectroscopy. A very fine correlation has been built in the electrical conductivity and FTIR result. On the basis of above finding, a prepared free standing solid polymeric film appears to be appropriate for the energy storage/conversion device applications.« less

Structural variability in Cu(I) and Ag(I) coordination polymers with a flexible dithione ligand: Synthesis, crystal structure, microbiological and theoretical studies

NASA Astrophysics Data System (ADS)

Beheshti, Azizolla; Nozarian, Kimia; Babadi, Susan Soleymani; Noorizadeh, Siamak; Motamedi, Hossein; Mayer, Peter; Bruno, Giuseppe; Rudbari, Hadi Amiri

2017-05-01

Two new compounds namely [Cu(SCN)(μ-L)]n (1) and {[Ag (μ2-L)](ClO4)}n (2) have been synthesized at room temperature by one-pot reactions between the 1,1-(1,4-butanediyl)bis(1,3-dihydro-3-methyl-1H-imidazole- 2-thione) (L) and appropriate copper(I) and silver(I) salts. These polymers have been characterized by single crystal X-ray diffraction, XRPD, TGA, elemental analysis, infrared spectroscopy, antibacterial activity and scanning probe microscopy studies. In the crystal structure of 1, copper atoms have a distorted trigonal planar geometry with a CuS2N coordination environment. Each of the ligands in the structure of 1 acting as a bidentate S-bridging ligand to form a 1D chain structure. Additionally, the adjacent 1D chains are interconnected by the intermolecular C-H…S interactions to create a 2D network structure. In contrast to 1, in the cationic 3D structure of 2 each of the silver atoms exhibits an AgS4 tetrahedral geometry with 4-membered Ag2S2 rings. In the structure of 2, the flexible ligand adopts two different conformations; gauche-anti-gauche and anti-anti-anti. The antibacterial studies of these polymers showed that polymer 2 is more potent antibacterial agent than 1. Scanning probe microscopy (SPM) study of the treated bacteria was carried out to investigate the structural changes cause by the interactions between the polymers and target bacteria. Theoretical study of polymer 1 investigated by the DFT calculations indicates that observed transitions at 266 nm and 302 nm in the UV-vis spectrum could be attributed to the π→π* and MLCT transitions, respectively.

Composite Materials Handbook. Volume 1. Polymer Matrix Composites Guidelines for Characterization of Structural Materials

DTIC Science & Technology

2002-06-17

power law type (References 6.8.6.1(h) and (i)). Various attempts have been made to use fracture mechanics based methods for predicting failure of...participate in the MIL-HDBK-17 coordination activity . 7. All information and data contained in this handbook have been coordinated with industry and the U.S...for statistically- based properties ............................. 6 2.2.3 Issues of data equivalence

Tuning the chromaticity of the emission color of the copolymers containing Eu(III), Tb(III), Be(II) ions based on colorimetric principle

NASA Astrophysics Data System (ADS)

Zhang, Aiqin; Yang, Yamin; Zhai, Guangmei; Jia, Husheng; Xu, Bingshe

2016-02-01

In this work, a method of tuning the chromaticity of the emission color of the copolymers containing Eu(III), Tb(III), Be(II) ions based on colorimetric principle was proposed. The technological route from coordination to copolymerization was employed to obtain the white light macromolecular phosphor. The three primary color monomers have been synthesized and their Commission Internationale de L'Eclairage (CIE) coordinates are respectively (0.540, 0.314), (0.231, 0.463), and (0.161, 0.054). The molar feed ratios of the three primary color monomers were calculated from the CIE coordinates based on colorimetric principle. Serial copolymers have been synthesized by free radical copolymerization of the three primary color monomers and methyl methacrylate. The quantum efficiency of the copolymers was higher than that of the complex monomers. The complexes were directly boned to the polymer chain, in which the energy transfer was reduced significantly compared to the doped-polymers. The experimental values of copolymers' CIE coordinates were located in the white light region in good agreement with theoretical values. The results indicate that the chromaticity of the emission color of the copolymers containing Eu(III), Tb(III), Be(II) ions could be tuned by theoretical calculation based on colorimetric principle.

Morphology design of porous coordination polymer crystals by coordination modulation.

PubMed

Umemura, Ayako; Diring, Stéphane; Furukawa, Shuhei; Uehara, Hiromitsu; Tsuruoka, Takaaki; Kitagawa, Susumu

2011-10-05

The design of crystal morphology, or exposed crystal facets, has enabled the development (e.g., catalytic activities, material attributes, and oriented film formation) of porous coordination polymers (PCPs) without changing material compositions. However, because crystal growth mechanisms are not fully understood, control of crystal morphology still remains challenging. Herein, we report the morphology design of [Cu(3)(btc)(2)](n) (btc = benzene-1,3,5-tricarboxylate) by the coordination modulation method (modulator = n-dodecanoic acid or lauric acid). A morphological transition (octahedron-cuboctahedron-cube) in the [Cu(3)(btc)(2)](n) crystal was observed with an increase in concentration of the modulator. By suitably defining a coarse-grained standard unit of [Cu(3)(btc)(2)](n) as its cuboctahedron main pore and determining its attachment energy on crystal surfaces, Monte Carlo coarse-grain modeling revealed the population and orientation of carboxylates and elucidated an important role of the modulator in determining the <100>- and <111>-growth throughout the crystal growth process. This comprehension, in fact, successfully led to designed crystal morphologies with oriented growth on bare substrates. Because selective crystal orientations on the bare substrates were governed by crystal morphology, this contribution also casts a new light on the unexplored issue of the significance of morphology design of PCPs.

Mixed ligand coordination polymers with flexible bis-imidazole linker and angular sulfonyldibenzoate: Crystal structure, photoluminescence and photocatalytic activity

NASA Astrophysics Data System (ADS)

Bisht, Kamal Kumar; Rachuri, Yadagiri; Parmar, Bhavesh; Suresh, Eringathodi

2014-05-01

Four ternary coordination polymers (CPs) namely, {[Ni(SDB)(BITMB)(H2O)]·H2O}n (CP1), {[Cd(SDB)(BITMB) (H2O)]·(THF)(H2O)}n (CP2), {[Zn2(SDB)2(BITMB)]·(THF)2}n (CP3) and {[Co2(SDB)2(BITMB)]·(Dioxane)3}n (CP4) composed of angular dicarboxylate SDB (4,4'-sulfonyldibenzoate) and N-donor BITMB (1,3-bis(imidazol-1-ylmethyl)-2,4,6-trimethyl benzene) have been synthesized by solvothermal reactions and characterized by single crystal X-ray diffraction and other physico-chemical techniques. CP1 possesses one-dimensional ribbon type metal-organic motifs glued together by H-bonds and π⋯π interactions, whereas CP2-CP4, exhibit non-interpenetrated sql networks supported by weak supramolecular interactions. Structural diversity of these CPs can be attributed to the coordination geometry adopted by the metal nodes, versatile coordination modes of SDB and conformational flexibility of BITMB. Solid state luminescence properties of CP1-CP4 were explored. Photocatalytic performance of all CPs for the decomposition of metanil yellow by dilute hydrogen peroxide in the presence of visible light was also investigated. 25-83% dye removal from aqueous solutions in the presence of CP1-CP4 was observed.

Anisotropic compressibility of the coordination polymer emim[Mn(btc)].

PubMed

Madsen, Solveig R; Moggach, Stephen A; Overgaard, Jacob; Brummerstedt Iversen, Bo

2016-06-01

The effect of pressure on the crystal structure of a coordination polymer, emim[Mn(II)(btc)] (emim = 1-ethyl,3-methyl imidazolium cation, btc = 1,3,5-benzene-tricarboxylate), was investigated with single-crystal X-ray diffraction. At 4.3 GPa the unit-cell volume had decreased by 14% compared with ambient conditions. The unit-cell contraction is highly anisotropic, with the a- and b-axes decreasing by 5.5 and 9.5%, respectively, and the c-axis compressing a mere 0.25% up to 1.7 GPa followed by a 0.2% expansion between 1.7 and 4.3 GPa. The 0.2% increase in length of the c-axis in this interval happens above the quasi-hydrostatic limit of the pressure-transmitting medium and therefore it might be a consequence of strain gradients. Under ambient conditions, two MnO6 units are connected by two carboxylate ligands to form dimeric units. On increasing pressure, a non-bonded O atom from a bridging carboxylate group approaches the Mn atom, with the Mn-O distance decreasing from 2.866 (1) Å at 0.3 GPa to 2.482 (6) Å at 4.3 GPa, increasing the coordination environment of the Mn ion from six- to seven-coordinated.

Rare earth niobate coordination polymers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muniz, Collin N.; Patel, Hiral; Fast, Dylan B.

Rare-earth (RE) coordination polymers are infinitely tailorable to yield luminescent materials for various applications. In this paper we described the synthesis of a heterometallic rare-earth coordination compound ((CH 3) 2SO) 3(RE)NbO(C 2O 4) 3 ((CH 3) 2SO) = dimethylsulfoxide, DMSO, (C 2O 2 = oxalate), (RE=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb). The structure was obtained from single crystal X-ray diffraction of the La analogue. The Nb =O and DMSO terminal-bonding character guides assembly of an open framework structure with noncentrosymmetric RE-coordination geometry, and large spacing between the RE centers. A second structure was observed by PXRD for themore » smaller rare earths (Dy, Ho, Er, Yb); this structure has not yet been determined. The materials were further characterized using FTIR, and photoluminescence measurements. Characteristic excitation and emission transitions were observed for RE = Nd, Sm, Eu, and Tb. Quantum yield (QY) measurements were performed by exciting Eu and Tb analoges at 394 nm (QY 66%) and 464 nm (QY 71%) for Eu; and 370 nm (QY=40%) for Tb. Finally, we attribute the high QY and bright luminescence to two main structure-function properties of the system; namely the absence of water in the structure, and absence of concentration quenching.« less

Rare earth niobate coordination polymers

DOE PAGES

Muniz, Collin N.; Patel, Hiral; Fast, Dylan B.; ...

2018-01-03

Rare-earth (RE) coordination polymers are infinitely tailorable to yield luminescent materials for various applications. In this paper we described the synthesis of a heterometallic rare-earth coordination compound ((CH 3) 2SO) 3(RE)NbO(C 2O 4) 3 ((CH 3) 2SO) = dimethylsulfoxide, DMSO, (C 2O 2 = oxalate), (RE=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb). The structure was obtained from single crystal X-ray diffraction of the La analogue. The Nb =O and DMSO terminal-bonding character guides assembly of an open framework structure with noncentrosymmetric RE-coordination geometry, and large spacing between the RE centers. A second structure was observed by PXRD for themore » smaller rare earths (Dy, Ho, Er, Yb); this structure has not yet been determined. The materials were further characterized using FTIR, and photoluminescence measurements. Characteristic excitation and emission transitions were observed for RE = Nd, Sm, Eu, and Tb. Quantum yield (QY) measurements were performed by exciting Eu and Tb analoges at 394 nm (QY 66%) and 464 nm (QY 71%) for Eu; and 370 nm (QY=40%) for Tb. Finally, we attribute the high QY and bright luminescence to two main structure-function properties of the system; namely the absence of water in the structure, and absence of concentration quenching.« less

A two-dimensional Zn coordination polymer with a three-dimensional supra-molecular architecture.

PubMed

Liu, Fuhong; Ding, Yan; Li, Qiuyu; Zhang, Liping

2017-10-01

The title compound, poly[bis-{μ 2 -4,4'-bis-[(1,2,4-triazol-1-yl)meth-yl]biphenyl-κ 2 N 4 : N 4' }bis-(nitrato-κ O )zinc(II)], [Zn(NO 3 ) 2 (C 18 H 16 N 6 ) 2 ] n , is a two-dimensional zinc coordination polymer constructed from 4,4'-bis-[(1 H -1,2,4-triazol-1-yl)meth-yl]-1,1'-biphenyl units. It was synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. The Zn II cation is located on an inversion centre and is coordinated by two O atoms from two symmetry-related nitrate groups and four N atoms from four symmetry-related 4,4'-bis-[(1 H -1,2,4-triazol-1-yl)meth-yl]-1,1'-biphenyl ligands, forming a distorted octa-hedral {ZnN 4 O 2 } coordination geometry. The linear 4,4'-bis-[(1 H -1,2,4-triazol-1-yl)meth-yl]-1,1'-biphenyl ligand links two Zn II cations, generating two-dimensional layers parallel to the crystallographic (132) plane. The parallel layers are connected by C-H⋯O, C-H⋯N, C-H⋯π and π-π stacking inter-actions, resulting in a three-dimensional supra-molecular architecture.

Bismuth as a versatile cation for luminescence in coordination polymers from BiX3/4,4'-bipy: understanding of photophysics by quantum chemical calculations and structural parallels to lanthanides.

PubMed

Sorg, Jens R; Wehner, Tobias; Matthes, Philipp R; Sure, Rebecca; Grimme, Stefan; Heine, Johanna; Müller-Buschbaum, Klaus

2018-05-16

Coordination polymers (CPs) with bismuth(iii) as a connectivity centre have been prepared from BiX3 (X = Cl-I) and 4,4'-bipyridine (bipy) in order to implement Bi-based luminescence. The products were obtained via different synthetic routes such as solution chemistry, melt syntheses or mechanochemical reactions. Five neutral and anionic 1D-CPs are presented that show a chemical parallel to trivalent lanthanides forming isostructural or closely related 1D-CPs, of which five additional compounds are described. Bi3+ proves to be a versatile cation for luminescence resulting from energy transfer processes between a metal and a ligand in the presented CPs. Quantum chemical calculations were carried out to investigate Bi3+-participation in the luminescence processes. The calculated results allow an assignment of the bright transitions composed of mainly metal-to-ligand-charge transfer (MLCT) character. These results show that Bi3+ can form strongly luminescent coordination compounds with N-donor ligands.

One-dimensional coordination polymers of whole row rare earth tris-pivalates

NASA Astrophysics Data System (ADS)

Tsymbarenko, Dmitry; Martynova, Irina; Grebenyuk, Dimitry; Shegolev, Vsevolod; Kuzmina, Natalia

2018-02-01

Fourteen 1D coordination polymers of rare earth pivalates [Ln(Piv)3]∞ (Ln = Y, La, Pr, Nd, Sm-Lu) were synthesized and characterized by powder X-ray diffraction, IR spectroscopy, TGA, and conventional elemental analysis. Crystal structures of [La(Piv)3]∞, [Yb(Piv)3]∞, [Lu(Piv)3]∞ were determined by means of single crystal X-ray analysis at 120 K, those of [Y(Piv)3]∞ and [Ho(Piv)3]∞ - from powder XRD data at 293 K. Transformation of [Ln(Piv)3]∞ structure and Piv- anions coordination mode along the whole row has been derived from powder XRD and IR spectroscopy results, and shown to crucially affect the relative location of 1D chains in the crystal structure, as well as the Ln···Ln distance within the single chain. Negative thermal expansion along 1D [Ln(Piv)3]∞ chain was revealed for Ln = Tm, Yb, Lu. Enforcement of 1D polymeric structure with the decrease of Ln ionic radius has been established from solid-state DFT calculations.

Air and moisture stable covalently-bonded tin(ii) coordination polymers.

PubMed

de Lima, G M; Walton, R I; Clarkson, G J; Bitzer, R S; Ardisson, J D

2018-06-05

Four covalently-bonded tin(ii) coordination polymers, (1)-(4), were hydrothermally prepared in aqueous alkaline media by the reactions of SnSO4 with 1,2,4,5-benzenetetracarboxylic acid (1), 1,3,5-benzenetricarboxylic acid (2), 4-hydroxypyridine-2,6-dicarboxylic acid (3), and 1,3,5-cyclohexanetricarboxylic acid (4). All products were structurally authenticated by single-crystal X-ray diffraction, and the number of different tin centres and their oxidation states were confirmed by 119Sn Mössbauer spectroscopy. In addition, the comparison between experimental and simulated X-ray powder diffraction patterns confirmed the authenticity of the samples. Our crystallographic results for (1)-(4) show that the Sn(ii) centres are tetracoordinated and exhibit distorted disphenoidal geometries, corroborating the presence of one stereochemically active lone electron pair at each metal site. Products (1) and (2) display bi-dimensional polymeric structures, (3) exhibits a one-dimensional architecture, whereas (4) shows a remarkable three-dimensional coordination network. Hirshfeld surface and supramolecular analyses for the repeating units of (1)-(4) were also performed in order to identify structurally important non-covalent interactions.

Investigation of cyano-bridged coordination nanoparticles Gd3+/[Fe(CN)6]3-/d-mannitol as T1-weighted MRI contrast agents

NASA Astrophysics Data System (ADS)

Perrier, M.; Gallud, A.; Ayadi, A.; Kennouche, S.; Porredon, C.; Gary-Bobo, M.; Larionova, J.; Goze-Bac, Ch.; Zanca, M.; Garcia, M.; Basile, I.; Long, J.; de Lapuente, J.; Borras, M.; Guari, Y.

2015-07-01

Cyano-bridged Gd3+/[Fe(CN)6]3- coordination polymer nanoparticles of 3-4 nm stabilized with d-mannitol presenting a high r1 relaxivity value of 11.4 mM-1 s-1 were investigated in vivo as contrast agents (CA) for Magnetic Resonance Imaging (MRI). They allow an increase of the MR image contrast and can act as an efficient intravascular T1 CA with a relatively long blood-circulation lifetime (60 min) without specific toxicity.Cyano-bridged Gd3+/[Fe(CN)6]3- coordination polymer nanoparticles of 3-4 nm stabilized with d-mannitol presenting a high r1 relaxivity value of 11.4 mM-1 s-1 were investigated in vivo as contrast agents (CA) for Magnetic Resonance Imaging (MRI). They allow an increase of the MR image contrast and can act as an efficient intravascular T1 CA with a relatively long blood-circulation lifetime (60 min) without specific toxicity. Electronic supplementary information (ESI) available: Experimental details and procedures, toxicological data, physical characterization. See DOI: 10.1039/c5nr01557j

Design of Deformation Monitoring System for Volcano Mitigation

NASA Astrophysics Data System (ADS)

Islamy, M. R. F.; Salam, R. A.; Munir, M. M.; Irsyam, M.; Khairurrijal

2016-08-01

Indonesia has many active volcanoes that are potentially disastrous. It needs good mitigation systems to prevent victims and to reduce casualties from potential disaster caused by volcanoes eruption. Therefore, the system to monitor the deformation of volcano was built. This system employed telemetry with the combination of Radio Frequency (RF) communications of XBEE and General Packet Radio Service (GPRS) communication of SIM900. There are two types of modules in this system, first is the coordinator as a parent and second is the node as a child. Each node was connected to coordinator forming a Wireless Sensor Network (WSN) with a star topology and it has an inclinometer based sensor, a Global Positioning System (GPS), and an XBEE module. The coordinator collects data to each node, one a time, to prevent collision data between nodes, save data to SD Card and transmit data to web server via GPRS. Inclinometer was calibrated with self-built in calibrator and tested in high temperature environment to check the durability. The GPS was tested by displaying its position in web server via Google Map Application Protocol Interface (API v.3). It was shown that the coordinator can receive and transmit data from every node to web server very well and the system works well in a high temperature environment.

Syntheses, structures and luminescent properties of two novel Zn (II) coordination polymers

NASA Astrophysics Data System (ADS)

Huang, Ya-Ru; Gao, Ling-Ling; Wang, Xiao-Qing; Fan, Li-Ming; Hu, Tuo-Ping

2018-02-01

Two new coordination polymers, namely [Zn(TZMB)]n (1) and {[Zn(TZMB)](H2TZMB)]·(C2H5OH)0.5(H2O)2.5}n (2), (H2TZMB = 4,4‧-(1H-1,2,4-triazol-1-yl)methylene-bis(benzonic acid), have been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction analysis, elemental analysis (EA), IR spectrum analysis (IR), powder X-ray diffraction (PXRD), and thermogravimetric (TG) analysis. Single X-ray diffraction analysis reveals that complex 1 is a 3D 3,6-connected net with the point symbol of (6110.84)(63)2 and complex 2 is a 2D 3-connected net with the point symbol of (63). Furthermore, luminescent properties of complexes 1 and 2 were also investigated in detail.

Mercury coordination polymers with flexible ethane-1,2-diyl-bis-(pyridyl-3-carboxylate): Synthesis, structures, thermal and luminescent properties

NASA Astrophysics Data System (ADS)

Vallejos, Javier; Brito, Iván; Cárdenas, Alejandro; Llanos, Jaime; Bolte, Michael; López-Rodríguez, Matías

2015-03-01

The reaction of the flexible ligand, ethane-1,2-diyl-bis-(pyridyl-3-carboxylate), (L) with HgI2 and HgBr2 salts under the same experimental conditions leads to the formation of two coordination polymers with different motifs: {[Hg(L)(Br2)]}n(1) and {[Hg(L)(I2)]}n(2). In both compounds, the ligand, (L) acts in a μ2-N:N‧-bidentate fashion to link HgBr2 and HgI2 units to form a linear and helical chain motif, along [1 0 0] for (1) and [0 0 1] for (2). The ethylene moiety of (L) has gauche and trans conformation in compounds (1) and (2), respectively. The flexible conformation of L produces differences in the optical and crystal properties of the two compounds.

A robust viologen and Mn-based porous coordination polymer with two types of Lewis acid sites providing high affinity for H2O, CO2 and NH3.

PubMed

Leblanc, A; Mercier, N; Allain, M; Dul, M-C; Weber, G; Geoffroy, N; Bellat, J-P; Bezverkhyy, I

2017-11-21

A novel porous coordination polymer [Mn(pc3)(H 2 O) 2 ]·xH 2 O (3 < x < 4) is synthesized in water at pH = 7 using the anionic viologen-carboxylate ligand 4,4'-bipyridinium,1,1'-bis-(2,4-dicarboxyphenyl) (pc3 2- ). Dehydration of the material results in the formation of open pores containing two types of accessible Lewis acid sites: exposed Mn 2+ cations and N + atoms of viologen units. Due to this property the PCP shows high affinity and capacity in the adsorption of H 2 O, CO 2 and NH 3 . Despite the presence of strong adsorption sites this material is stable in liquid water and in gaseous NH 3 .

Weak cooperativity in selected iron(II) 1D coordination polymers

NASA Astrophysics Data System (ADS)

Dîrtu, Marinela M.; Gillard, Damien; Naik, Anil D.; Rotaru, Aurelian; Garcia, Yann

2012-03-01

The spin crossover behaviour of a new class of FeII coordination polymers [Fe(phtptrz)3]I2 ( 1), [Fe(phtptrz)3](ReO4)2•CH3OH ( 2) and [Fe(phtptrz)3]TaF7•6H2O ( 3) based on a novel ligand 4-(3' -N-phtalimido-propyl)-1,2,4-triazole (phtptrz), were investigated by temperature dependent 57Fe Mössbauer spectroscopy and magnetic susceptibility measurements. The adverse effect of bulky substituent on 1,2,4-triazole, favorable supramolecular interactions and influence of increasing anion size on spin crossover profile is discussed. 1 and 2 show thermally induced spin conversions of gradual and incomplete nature with associated thermochromism, and transition temperatures T1/2 ~ 163 K and 137 K, respectively. A spin state crossover is also identified for 3.

Coordination Polymerization of Renewable 3-Methylenecyclopentene with Rare-Earth-Metal Precursors.

PubMed

Liu, Bo; Li, Shihui; Wang, Meiyan; Cui, Dongmei

2017-04-10

Coordination polymerization of renewable 3-methylenecyclopentene has been investigated for the first time using rare-earth metal-based precursors bearing various bulky ligands. All the prepared complexes catalyze controllable polymerization of 3-methylenecyclopentene into high molecular weight polymers, of which the NPN- and NSN-tridentate non-Cp ligated lutetium-based catalytic systems exhibited extremely high activities up to 11 520 kg/(mol Lu ⋅h) in a dilute toluene solution (3.2 g/100 mL) at room temperature. The resultant polymers have pure 1,4-regioregularity (>99 %) and tailorable number average molecular weights (1-20×10 4 ) with narrow molecular weight distributions (polydispersity index (PDI)=1.45-1.79). DFT simulations were employed to study the polymerization mechanism and stereoregularity control. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Two novel penetrating coordination polymers based on flexible S-containing dicarboxylate acid with sensing properties towards Fe3+ and Cr2O72- ions

NASA Astrophysics Data System (ADS)

Chen, Zhiwei; Mi, Xiuna; Wang, Suna; Lu, Jing; Li, Yunwu; Li, Dacheng; Dou, Jianmin

2018-05-01

Two new coordination polymers (CPs), namely, {[Zn(L)(bpp)]·DMF}n (1) and {[Zn(L)(bpe)]·DMF}n (2) (L = 2,2'-[benzene-1,3-diylbis(methanediylsulfanediyl)]dibenzoic acid, bpp= 1,3-bis(4-pyridyl)propane, bpe = 1,2-Bis(4-pyridyl)ethylene, DMF = N,N-Dimethylformamide), have been solvothermally synthesized and fully characterized. Complex 1 displays a 2D→2D three-fold"false" interpenetrating structure while complex 2 possesses a novel 3-D 4-connected structure with fascinating self-penetrating moieties. The luminescence studies reveal that these complexes exhibited excellent selectivity for Fe3+ and Cr2O72- ions in DMF. The sensing mechanism was investigated through PXRD, XPS , EDS mapping measurements, and discussed in details.

New Ag(I)-iminophosphorane coordination polymers as efficient catalysts precursors for the MW-assisted Meyer-Schuster rearrangement of propargylic alcohols in water.

PubMed

García-Álvarez, Joaquín; Díez, Josefina; Vidal, Cristian; Vicent, Cristian

2013-06-03

Treatment of the N-thiophosphorylated iminophosphorane ligands (PTA)═NP(═S)(OR)2 [PTA = 1,3,5-triaza-7-phosphaadamantane, 3a and 3b] and (DAPTA)═NP(═S)(OR)2 [DAPTA = 3,7-diacetyl-1,3,7-triaza-5-bicyclo[3.3.1]nonane, 4a and 4b] with an equimolecular amount of AgSbF6 leads to high-yield formation of the new one-dimensional coordination polymers [Ag{μ(2)-N,S-(PTA)═NP(═S)(OR)2}]x[SbF6]x (5a and 5b) and [Ag{μ(2)-O,S-(DAPTA)═NP(═S)(OR)2}]x[SbF6]x (6a and 6b), respectively. These new (iminophosphorane)silver(I) coordination polymers are efficient catalyst precursors for the Meyer-Schuster isomerization of both terminal and internal alkynols. Reactions proceeded in water, under aerobic conditions and using microwave irradiation as heating source, to afford the corresponding α,β-unsaturated carbonyl compounds in excellent yields, without the addition of any cocatalyst. Remarkably, it should be noted that this catalytic system can be recycled up to 10 consecutive runs (1st cycle 45 min, 99%; 10th cycle 6 h, 97%). ESI-MS analysis of 5a in water has been carried out providing valuable insight into the monomeric active species responsible for catalytic activity in water.

Design and Synthesis of a Biocompatible 1D Coordination Polymer as Anti-Breast Cancer Drug Carrier, 5-Fu: In Vitro and in Vivo Studies.

PubMed

Rezaei, Mahsa; Abbasi, Alireza; Dinarvand, Rassoul; Jeddi-Tehrani, Mahmood; Janczak, Jan

2018-05-17

Designable coordination polymers with suitable chemical diversities and biocompatible structures have been proposed as a promising class of vehicles for drug delivery systems. Here, we hydrothermally synthesized a novel one-dimensional (1D) coordination polymer, [Zn(H 2 O) 6 K 2 (H 2 BTC) 2 (H 2 O) 4 ](H 2 BTC) 2 ·2H 2 O, where H 3 BTC = benzene-1,3,5-tricarboxylic acid (trimesic acid), cp.1. As the hydrogen bonds stabilized 1D chains in three dimensions, the cp.1 could be a good candidate for delivering small-molecule chemotherapeutics such as 5-fluorouracil (5-Fu). The synthesized cp.1 showed a remarkable 5-Fu loading of 66% with encapsulation efficiency of 98% and almost complete release process. The 5-Fu-loaded cp.1 displayed a time-dependent cytotoxicity effect against breast cancer cell lines MCF-7 and 4T1. The cellular uptake of cp.1 particles was investigated via confocal laser scanning microscopy using fluorescein isothiocyanate and LysoTracker Red staining. Furthermore, the in vivo antitumor impact of 5-Fu-loaded cp.1 was studied on 4T1 breast cancer BALB/c mice model. The intratumor treatment of 5-Fu-loaded cp.1 demonstrated beneficial antitumor efficacy by postponing tumor growth. These results suggest that the 5-Fu-loaded cp.1 microparticles with a great locoregional delivery can be efficient anticancer drug carriers for further clinical treatments.

Radiation processing of natural polymers: The IAEA contribution

NASA Astrophysics Data System (ADS)

Haji-Saeid, Mohammad; Safrany, Agnes; Sampa, Maria Helena de O.; Ramamoorthy, Natesan

2010-03-01

Radiation processing offers a clean and additive-free method for preparation of value-added novel materials based on renewable, non-toxic, and biodegradable natural polymers. Crosslinked natural polymers can be used as hydrogel wound dressings, face cleaning cosmetic masks, adsorbents of toxins, and non-bedsore mats; while low molecular weight products show antibiotic, antioxidant, and plant-growth promoting properties. Recognizing the potential benefits that radiation technology can offer for processing of natural polymers into useful products, the IAEA implemented a coordinated research project (CRP) on "Development of Radiation-processed products of Natural Polymers for application in Agriculture, Healthcare, Industry and Environment". This CRP was launched at the end of 2007 with participation of 16 MS to help connecting radiation technology and end-users to derive enhanced benefits from these new value-added products of radiation-processed natural materials. In this paper the results of activities in participating MS related to this work will be presented.

Constitutive Modeling of Nanotube/Polymer Composites with Various Nanotube Orientations

NASA Technical Reports Server (NTRS)

Odegard, Gregory M.; Gates, Thomas S.

2002-01-01

In this study, a technique has been proposed for developing constitutive models for polymer composite systems reinforced with single-walled carbon nanotubes (SWNT) with various orientations with respect to the bulk material coordinates. A nanotube, the local polymer adjacent to the nanotube, and the nanotube/polymer interface have been modeled as an equivalent-continuum fiber by using an equivalent-continuum modeling method. The equivalent-continuum fiber accounts for the local molecular structure and bonding information and serves as a means for incorporating micromechanical analyses for the prediction of bulk mechanical properties of SWNT/polymer composite. As an example, the proposed approach is used for the constitutive modeling of a SWNT/LaRC-SI (with a PmPV interface) composite system, with aligned nanotubes, three-dimensionally randomly oriented nanotubes, and nanotubes oriented with varying degrees of axisymmetry. It is shown that the Young s modulus is highly dependent on the SWNT orientation distribution.

Local-feature analysis for automated coarse-graining of bulk-polymer molecular dynamics simulations.

PubMed

Xue, Y; Ludovice, P J; Grover, M A

2012-12-01

A method for automated coarse-graining of bulk polymers is presented, using the data-mining tool of local feature analysis. Most existing methods for polymer coarse-graining define superatoms based on their covalent bonding topology along the polymer backbone, but here superatoms are defined based only on their correlated motions, as observed in molecular dynamics simulations. Correlated atomic motions are identified in the simulation data using local feature analysis, between atoms in the same or in different polymer chains. Groups of highly correlated atoms constitute the superatoms in the coarse-graining scheme, and the positions of their seed coordinates are then projected forward in time. Based on only the seed positions, local feature analysis enables the full reconstruction of all atomic positions. This reconstruction suggests an iterative scheme to reduce the computation of the simulations to initialize another short molecular dynamic simulation, identify new superatoms, and again project forward in time.

Diagnostics of transparent polymer coatings of metal items

NASA Astrophysics Data System (ADS)

Varepo, L. G.; Ermakova, I. N.; Nagornova, I. V.; Kondratov, A. P.

2017-08-01

The methods of visual and instrumental express diagnostics of safety critical defects and non-uniform thickness of transparent mono- and multilayer polyolefin surface coating of metal items are analyzed in the paper. The instrumental diagnostics method relates to colorimetric measuring based on effects, which appear in the polarized light for extrusion polymer coatings. A color coordinates dependence (in the color system CIE La*b*) on both HDPE / PVC coating thickness fluctuation values (from average ones) and coating interlayer or adhesion layer delaminating is shown. A variation of color characteristics in the polarized light at a liquid penetration into delaminated polymer layers is found. Measuring parameters and critical uncertainties are defined.

Arm retraction dynamics of entangled star polymers: A forward flux sampling method study

NASA Astrophysics Data System (ADS)

Zhu, Jian; Likhtman, Alexei E.; Wang, Zuowei

2017-07-01

The study of dynamics and rheology of well-entangled branched polymers remains a challenge for computer simulations due to the exponentially growing terminal relaxation times of these polymers with increasing molecular weights. We present an efficient simulation algorithm for studying the arm retraction dynamics of entangled star polymers by combining the coarse-grained slip-spring (SS) model with the forward flux sampling (FFS) method. This algorithm is first applied to simulate symmetric star polymers in the absence of constraint release (CR). The reaction coordinate for the FFS method is determined by finding good agreement of the simulation results on the terminal relaxation times of mildly entangled stars with those obtained from direct shooting SS model simulations with the relative difference between them less than 5%. The FFS simulations are then carried out for strongly entangled stars with arm lengths up to 16 entanglements that are far beyond the accessibility of brute force simulations in the non-CR condition. Apart from the terminal relaxation times, the same method can also be applied to generate the relaxation spectra of all entanglements along the arms which are desired for the development of quantitative theories of entangled branched polymers. Furthermore, we propose a numerical route to construct the experimentally measurable relaxation correlation functions by effectively linking the data stored at each interface during the FFS runs. The obtained star arm end-to-end vector relaxation functions Φ (t ) and the stress relaxation function G(t) are found to be in reasonably good agreement with standard SS simulation results in the terminal regime. Finally, we demonstrate that this simulation method can be conveniently extended to study the arm-retraction problem in entangled star polymer melts with CR by modifying the definition of the reaction coordinate, while the computational efficiency will depend on the particular slip-spring or slip-link model employed.

White polymer light-emitting diodes based on star-shaped polymers with an orange dendritic phosphorescent core.

PubMed

Zhu, Minrong; Li, Yanhu; Cao, Xiaosong; Jiang, Bei; Wu, Hongbin; Qin, Jingui; Cao, Yong; Yang, Chuluo

2014-12-01

A series of new star-shaped polymers with a triphenylamine-based iridium(III) dendritic complex as the orange-emitting core and poly(9,9-dihexylfluorene) (PFH) chains as the blue-emitting arms is developed towards white polymer light-emitting diodes (WPLEDs). By fine-tuning the content of the orange phosphor, partial energy transfer and charge trapping from the blue backbone to the orange core is realized to achieve white light emission. Single-layer WPLEDs with the configuration of ITO (indium-tin oxide)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/polymer/CsF/Al exhibit a maximum current efficiency of 1.69 cd A(-1) and CIE coordinates of (0.35, 0.33), which is very close to the pure white-light point of (0.33, 0.33). To the best of our knowledge, this is the first report on star-shaped white-emitting single polymers that simultaneously consist of fluorescent and phosphorescent species. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Structure and mechanisms underlying ion transport in ternary polymer electrolytes containing ionic liquids

NASA Astrophysics Data System (ADS)

Mogurampelly, Santosh; Ganesan, Venkat

2017-02-01

We use all atom molecular dynamics simulations to investigate the influence of 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6) ionic liquid on the structure and transport properties of poly(ethylene oxide) (PEO) polymer electrolytes doped with LiPF6 salt. We observe enhanced diffusivities of the Li+, PF6-, and BMIM+ ions with increasing loading of the ionic liquid. Interplay between the different ion-ion and ion-polymer interactions is seen to lead to a destabilization of the Li-PF6 coordination and increase in the strength of association between the Li+ cations and the polymer backbone. As a consequence, the polymer segmental relaxation times are shown to be only moderately affected by the addition of ionic liquids. The ionic-liquid induced changes in the mobilities of Li+ ions are seen to be correlated to polymer segmental relaxation times. However, the mobilities of BMIM+ ions are seen to be more strongly correlated to the BMIM-PF6 ion-pair relaxation times.

Investigating the geometrical preferences of a flexible benzimidazolone-based linker in the synthesis of coordination polymers

PubMed Central

Jones, Corey L.; Marsden, Elizabeth A.; Nevin, Adam C.; Kariuki, Benson M.; Bhadbhade, Mohan M.; Martin, Adam D.

2017-01-01

A series of new group 2 coordination polymers, MgL ={MgL(H2O)(DMF)0.75}∞, CaL = {CaL(DMF)2}∞, SrL = {SrL(H2O)0.5}∞ and BaL = {BaL(H2O)0.5}∞, were synthesized using a flexible benzimidazolone diacetic acid linker (H2L) in which the two carboxylic acid binding sites are connected to a planar core via {–CH2–} spacers that can freely rotate in solution. In a ‘curiosity-led' diversion from group 2 metals, the first row transition metal salts Mn2+, Cu2+ and Zn2+ were also reacted with L to yield crystals of MnL = {MnL(DMF)(H2O)3.33}∞, Cu3L2 = {Cu3L2(DMF)2(CHO2)2}∞ and ZnL = {ZnL(DMF)}∞. Crystal structures were obtained for all seven materials. All structures form as two-dimensional sheets and contain six-coordinate centres, with the exception of ZnL, which displays tetrahedrally coordinated metal centres, and Cu3L2, which contains square planar coordinated metal centres and Cu paddle-wheels. In each structure, the linker adopts one of two distinct conformations, with the carboxylate groups either cis or trans with respect to the planar core. All materials were also characterized by powder X-ray diffraction and thermogravimetric analysis. PMID:29308246

Heterobimetallic thiocyanato-bridged coordination polymers based on [Hg(SCN) 4] 2-: Synthesis, crystal structure, magnetic properties and ESR studies

NASA Astrophysics Data System (ADS)

Jian, Fang-Fang; Xiao, Hai-Lian; Liu, Fa Qian

2006-12-01

Three new M/Hg bimetallic thiocyanato-bridged coordination polymers; [Hg(SCN) 4Ni(Im) 3] ∞1, [Hg(SCN) 4Mn(Im) 2] ∞2, and [Hg(SCN) 4Cu(Me-Im) 2 Hg(SCN) 4Cu(Me-Im) 4] ∞3, (Im=imidazole, Me-Im= N-methyl-imidazole), have been synthesized and characterized by means of elemental analysis, ESR, and single-crystal X-ray. X-ray diffraction analysis reveals that these three complexes all form 3D network structure, and their structures all contain a thiocyanato-bridged Hg⋯M⋯Hg chain ( M=Mn, Ni, Cu) in which the metal and mercury centers exhibit different coordination environments. In complex 1, the [Hg(SCN) 4] 2- anion connects three [Ni(Im) 3] 2+ using three SCN ligands giving rise to a 3D structure, and in complex 2, four SCN ligands bridge [Hg(SCN) 4] 2- and [Mn(Im) 2] 2+ to form a 3D structure. The structure of 3 contains two copper atoms with distinct coordination environment; one is coordinated by four N-methyl-imidazole ligands and two axially elongated SCN groups, and another by four SCN groups (two elongated) and two N-methyl-imidazole ligands. The magnetic property of complex 1 has been investigated. The spin state structure in hetermetallic NiHgNi systems of complex 1 is irregular. The ESR spectra results of complex 3 demonstrate Cu 2+ ion lie on octahedral environment.

The coordination behaviour of ferrocene-based pyridylphosphine ligands towards Zn(II), Cd(II) and Hg(II).

PubMed

Siemeling, Ulrich; Klemann, Thorsten; Bruhn, Clemens; Schulz, Jiří; Štěpnička, Petr

2011-05-07

The reaction of Group 12 metal dihalides MX(2) with the P,N-ligands [Fe(C(5)H(4)-PPh(2))(C(5)H(4)-2-py)] (1) (2-py = pyrid-2-yl), [Fe(C(5)H(4)-PPh(2))(C(5)H(4)-CH(2)-2-py)] (2) and [Fe(C(5)H(4)-PPh(2))(C(5)H(4)-3-py)] (3) (3-py = pyrid-3-yl) was investigated. For a 1 : 1 molar ratio of MX(2) and the respective ligand, three structure types were found in the solid state, viz. chelate, cyclic dimer and chain-like coordination polymer. The M(II) coordination environment is distorted pseudo-tetrahedral in each case. The P-M-N angle is much larger in the chelates (≥119°) than in the ligand-bridged structures (≤109°). 1 prefers the formation of chelates [MX(2)(1-κ(2)N,P)]. 3 forms coordination polymers [MX(2)(μ-3)](n). With the more flexible 2 all three structure types can occur. Dynamic coordination equilibria were observed in solution for the molecular complexes obtained with 1 and 2. NMR data indicate that the N- and P-donor sites interact most strongly with Zn(II) and Hg(II), respectively. While the formation of bis(phosphine)mercury complexes (soft-soft) was easily achieved, no bis(pyridine)zinc complex (borderline-borderline) could be obtained, which is surprising in view of the HSAB principle.

Stigmergic construction and topochemical information shape ant nest architecture

PubMed Central

Khuong, Anaïs; Gautrais, Jacques; Perna, Andrea; Sbaï, Chaker; Combe, Maud; Kuntz, Pascale; Jost, Christian; Theraulaz, Guy

2016-01-01

The nests of social insects are not only impressive because of their sheer complexity but also because they are built from individuals whose work is not centrally coordinated. A key question is how groups of insects coordinate their building actions. Here, we use a combination of experimental and modeling approaches to investigate nest construction in the ant Lasius niger. We quantify the construction dynamics and the 3D structures built by ants. Then, we characterize individual behaviors and the interactions of ants with the structures they build. We show that two main interactions are involved in the coordination of building actions: (i) a stigmergic-based interaction that controls the amplification of depositions at some locations and is attributable to a pheromone added by ants to the building material; and (ii) a template-based interaction in which ants use their body size as a cue to control the height at which they start to build a roof from existing pillars. We then develop a 3D stochastic model based on these individual behaviors to analyze the effect of pheromone presence and strength on construction dynamics. We show that the model can quantitatively reproduce key features of construction dynamics, including a large-scale pattern of regularly spaced pillars, the formation and merging of caps over the pillars, and the remodeling of built structures. Finally, our model suggests that the lifetime of the pheromone is a highly influential parameter that controls the growth and form of nest architecture. PMID:26787857

Stigmergic construction and topochemical information shape ant nest architecture.

PubMed

Khuong, Anaïs; Gautrais, Jacques; Perna, Andrea; Sbaï, Chaker; Combe, Maud; Kuntz, Pascale; Jost, Christian; Theraulaz, Guy

2016-02-02

The nests of social insects are not only impressive because of their sheer complexity but also because they are built from individuals whose work is not centrally coordinated. A key question is how groups of insects coordinate their building actions. Here, we use a combination of experimental and modeling approaches to investigate nest construction in the ant Lasius niger. We quantify the construction dynamics and the 3D structures built by ants. Then, we characterize individual behaviors and the interactions of ants with the structures they build. We show that two main interactions are involved in the coordination of building actions: (i) a stigmergic-based interaction that controls the amplification of depositions at some locations and is attributable to a pheromone added by ants to the building material; and (ii) a template-based interaction in which ants use their body size as a cue to control the height at which they start to build a roof from existing pillars. We then develop a 3D stochastic model based on these individual behaviors to analyze the effect of pheromone presence and strength on construction dynamics. We show that the model can quantitatively reproduce key features of construction dynamics, including a large-scale pattern of regularly spaced pillars, the formation and merging of caps over the pillars, and the remodeling of built structures. Finally, our model suggests that the lifetime of the pheromone is a highly influential parameter that controls the growth and form of nest architecture.

Bioreducible Zinc(II)-Coordinative Polyethylenimine with Low Molecular Weight for Robust Gene Delivery of Primary and Stem Cells.

PubMed

Liu, Shuai; Zhou, Dezhong; Yang, Jixiang; Zhou, Hao; Chen, Jiatong; Guo, Tianying

2017-03-30

To transform common low-molecular-weight (LMW) cationic polymers, such as polyethylenimine (PEI), to highly efficient gene vectors would be of great significance but remains challenging. Because LMW cationic polymers perform far less efficiently than their high-molecular-weight counterparts, mainly due to weaker nucleic acid encapsulation, herein we report the design and synthesis of a dipicolylamine-based disulfide-containing zinc(II) coordinative module (Zn-DDAC), which is used to functionalize LMW PEI (M w ≈ 1800 Da) to give a non-viral vector (Zn-PD) with high efficiency and safety in primary and stem cells. Given its high phosphate binding affinity, Zn-DDAC can significantly promote the DNA packaging functionality of PEI 1.8k and improve the cellular uptake of formulated polyplexes, which is particularly critical for hard-to-transfect cell types. Furthermore, Zn-PD polymer can be cleaved by glutathione in cytoplasm to facilitate DNA release post internalization and diminish the cytotoxicity. Consequently, the optimal Zn-PD mediates 1-2 orders of magnitude higher gluciferase activity than commercial transfection reagents, Xfect and PEI 25k , across diverse cell types, including primary and stem cells. Our findings provide a valuable insight into the exploitation of LMW cationic polymers for gene delivery and demonstrate great promise for the development of next-generation non-viral vectors for clinically viable gene therapy.

Metal coordination polymer derived mesoporous Co3O4 nanorods with uniform TiO2 coating as advanced anodes for lithium ion batteries

NASA Astrophysics Data System (ADS)

Geng, Hongbo; Ang, Huixiang; Ding, Xianguang; Tan, Huiteng; Guo, Guile; Qu, Genlong; Yang, Yonggang; Zheng, Junwei; Yan, Qingyu; Gu, Hongwei

2016-01-01

In this work, a one-dimensional Co3O4@TiO2 core-shell electrode material with superior electrochemical performance is fabricated by a convenient and controllable route. The approach involves two main steps: the homogeneous deposition of polydopamine and TiO2 layers in sequence on the cobalt coordination polymer and the thermal decomposition of the polymer matrix. The as-prepared electrode material can achieve excellent electrochemical properties and stability as an anode material for lithium ion batteries, such as a high specific capacity of 1279 mA h g-1, good cycling stability (around 803 mA h g-1 at a current density of 200 mA g-1 after 100 cycles), and stable rate performance (around 520 mA h g-1 at a current density of 1000 mA g-1). This dramatic electrochemical performance is mainly attributed to the excellent structural characteristics, which could improve the electrical conductivity and lithium ion mobility, as well as electrolyte permeability and architectural stability during cycling.In this work, a one-dimensional Co3O4@TiO2 core-shell electrode material with superior electrochemical performance is fabricated by a convenient and controllable route. The approach involves two main steps: the homogeneous deposition of polydopamine and TiO2 layers in sequence on the cobalt coordination polymer and the thermal decomposition of the polymer matrix. The as-prepared electrode material can achieve excellent electrochemical properties and stability as an anode material for lithium ion batteries, such as a high specific capacity of 1279 mA h g-1, good cycling stability (around 803 mA h g-1 at a current density of 200 mA g-1 after 100 cycles), and stable rate performance (around 520 mA h g-1 at a current density of 1000 mA g-1). This dramatic electrochemical performance is mainly attributed to the excellent structural characteristics, which could improve the electrical conductivity and lithium ion mobility, as well as electrolyte permeability and architectural stability during cycling. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr08570e

Summary report on the performance of open graded friction course quieter pavements : I-5 Lynnwood, SR-520 Medina, I-405 Bellevue.

DOT National Transportation Integrated Search

2013-09-01

This document summarizes the acoustic properties and pavement performance of three asphalt quieter pavement projects. Each of the projects included open graded friction course pavement built with sections of crumb rubber and polymer modified asphalt ...

The Lunar Space Elevator, a Near Term Means to Reduce Cost of Lunar Access

NASA Astrophysics Data System (ADS)

Radley, C. F.

2018-04-01

LSE built from existing commercial polymers, launched, and deployed for <$2B. Prototype weighing 48 tons with 100 kg payload pays for itself in 53 sample return cycles. Reduces the cost of soft landing on the Moon >3x, sample return cost >9x.

Charge Separation and Recombination at Polymer-Fullerene Heterojunctions: Delocalization and Hybridization Effects.

PubMed

D'Avino, Gabriele; Muccioli, Luca; Olivier, Yoann; Beljonne, David

2016-02-04

We address charge separation and recombination in polymer/fullerene solar cells with a multiscale modeling built from accurate atomistic inputs and accounting for disorder, interface electrostatics and genuine quantum effects on equal footings. Our results show that bound localized charge transfer states at the interface coexist with a large majority of thermally accessible delocalized space-separated states that can be also reached by direct photoexcitation, thanks to their strong hybridization with singlet polymer excitons. These findings reconcile the recent experimental reports of ultrafast exciton separation ("hot" process) with the evidence that high quantum yields do not require excess electronic or vibrational energy ("cold" process), and show that delocalization, by shifting the density of charge transfer states toward larger effective electron-hole radii, may reduce energy losses through charge recombination.

Low Cost Polymer heat Exchangers for Condensing Boilers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Butcher, Thomas; Trojanowski, Rebecca; Wei, George

2015-09-30

Work in this project sought to develop a suitable design for a low cost, corrosion resistant heat exchanger as part of a high efficiency condensing boiler. Based upon the design parameters and cost analysis several geometries and material options were explored. The project also quantified and demonstrated the durability of the selected polymer/filler composite under expected operating conditions. The core material idea included a polymer matrix with fillers for thermal conductivity improvement. While the work focused on conventional heating oil, this concept could also be applicable to natural gas, low sulfur heating oil, and biodiesel- although these are considered tomore » be less challenging environments. An extruded polymer composite heat exchanger was designed, built, and tested during this project, demonstrating technical feasibility of this corrosion-resistant material approach. In such flue gas-to-air heat exchangers, the controlling resistance to heat transfer is in the gas-side convective layer and not in the tube material. For this reason, the lower thermal conductivity polymer composite heat exchanger can achieve overall heat transfer performance comparable to a metal heat exchanger. However, with the polymer composite, the surface temperature on the gas side will be higher, leading to a lower water vapor condensation rate.« less

Artificial neural network based particle size prediction of polymeric nanoparticles.

PubMed

Youshia, John; Ali, Mohamed Ehab; Lamprecht, Alf

2017-10-01

Particle size of nanoparticles and the respective polydispersity are key factors influencing their biopharmaceutical behavior in a large variety of therapeutic applications. Predicting these attributes would skip many preliminary studies usually required to optimize formulations. The aim was to build a mathematical model capable of predicting the particle size of polymeric nanoparticles produced by a pharmaceutical polymer of choice. Polymer properties controlling the particle size were identified as molecular weight, hydrophobicity and surface activity, and were quantified by measuring polymer viscosity, contact angle and interfacial tension, respectively. A model was built using artificial neural network including these properties as input with particle size and polydispersity index as output. The established model successfully predicted particle size of nanoparticles covering a range of 70-400nm prepared from other polymers. The percentage bias for particle prediction was 2%, 4% and 6%, for the training, validation and testing data, respectively. Polymer surface activity was found to have the highest impact on the particle size followed by viscosity and finally hydrophobicity. Results of this study successfully highlighted polymer properties affecting particle size and confirmed the usefulness of artificial neural networks in predicting the particle size and polydispersity of polymeric nanoparticles. Copyright © 2017 Elsevier B.V. All rights reserved.

Fabrication and evaluation of polymeric early-warning fire-alarm devices. [combustion products

NASA Technical Reports Server (NTRS)

Senturia, S. D.

1975-01-01

The electrical resistivities were investigated of some polymers known to be enhanced by the presence of certain gases. This was done to make a device capable of providing early warning to fire through its response with the gases produced in the early phases of combustion. Eight polymers were investigated: poly(phenyl acetylene), poly(p-aminophenyl acetylene), poly(p-nitrophenyl acetylene), poly(p-formamidophenyl acetylene), poly(ethynyl ferrocene), poly(ethynyl carborane), poly(ethynyl pyridine), and the polymer made from 1,2,3,6 tetramethyl pyridazine. A total of 40 usable thin-film sandwich devices and a total of 70 usable interdigitated-electrode lock-and-key devices were fabricated. The sandwich devices were used for measurements of contact linearity, polymer conductivity, and polymer dielectric constant. The lock-and-key devices were used to determine the response of the polymers to a spectrum of gases that included ammonia, carbon nonoxide, carbon dioxide, sulfur dioxide, ethylene, acrolein, water vapor, and normal laboratory air. Strongest responses were to water vapor, ammonia, and acrolein, and depending on the polymer, weaker responses to carbon dioxide, sulfur dioxide, and carbon monoxide were observed. A quantitative theory of device operation, capable of accounting for observed device leakage current and sensitivity, was developed. A prototype detection/alarm system was designed and built for use in demonstrating sensor performance.

Investigating the Release of a Hydrophobic Peptide from Matrices of Biodegradable Polymers: An Integrated Method Approach

PubMed Central

Gubskaya, Anna V.; Khan, I. John; Valenzuela, Loreto M.; Lisnyak, Yuriy V.; Kohn, Joachim

2013-01-01

The objectives of this work were: (1) to select suitable compositions of tyrosine-derived polycarbonates for controlled delivery of voclosporin, a potent drug candidate to treat ocular diseases, (2) to establish a structure-function relationship between key molecular characteristics of biodegradable polymer matrices and drug release kinetics, and (3) to identify factors contributing in the rate of drug release. For the first time, the experimental study of polymeric drug release was accompanied by a hierarchical sequence of three computational methods. First, suitable polymer compositions used in subsequent neural network modeling were determined by means of response surface methodology (RSM). Second, accurate artificial neural network (ANN) models were built to predict drug release profiles for fifteen polymers located outside the initial design space. Finally, thermodynamic properties and hydrogen-bonding patterns of model drug-polymer complexes were studied using molecular dynamics (MD) technique to elucidate a role of specific interactions in drug release mechanism. This research presents further development of methodological approaches to meet challenges in the design of polymeric drug delivery systems. PMID:24039300

Polymers for Traveling Wave Ion Mobility Spectrometry Calibration

NASA Astrophysics Data System (ADS)

Duez, Quentin; Chirot, Fabien; Liénard, Romain; Josse, Thomas; Choi, ChangMin; Coulembier, Olivier; Dugourd, Philippe; Cornil, Jérôme; Gerbaux, Pascal; De Winter, Julien

2017-07-01

One of the main issues when using traveling wave ion mobility spectrometry (TWIMS) for the determination of collisional cross-section (CCS) concerns the need for a robust calibration procedure built from referent ions of known CCS. Here, we implement synthetic polymer ions as CCS calibrants in positive ion mode. Based on their intrinsic polydispersities, polymers offer in a single sample the opportunity to generate, upon electrospray ionization, numerous ions covering a broad mass range and a large CCS window for different charge states at a time. In addition, the key advantage of polymer ions as CCS calibrants lies in the robustness of their gas-phase structure with respect to the instrumental conditions, making them less prone to collisional-induced unfolding (CIU) than protein ions. In this paper, we present a CCS calibration procedure using sodium cationized polylactide and polyethylene glycol, PLA and PEG, as calibrants with reference CCS determined on a home-made drift tube. Our calibration procedure is further validated by testing the polymer calibration to determine CCS of numerous different ions for which CCS are reported in the literature. [Figure not available: see fulltext.

Poly[[sesqui[mu2-1,4-bis(imidazol-1-ylmethyl)benzene-kappa(2)N:N'](carbonato-kappa(2)O,O')copper(II)] 1,4-bis(imidazol-1-ylmethyl)benzene hemisolvate pentahydrate].

PubMed

Dai, Yu-Mei; Tang, En; Huang, Jin-Feng; Yang, Qiu-Yan

2008-10-01

The asymmetric unit of the title compound, {[Cu(CO(3))(C(14)H(14)N(4))(1.5)] x 0.5 C(14)H(14)N(4) x 5 H(2)O}(n), contains one Cu(II) cation in a slightly distorted square-pyramidal coordination environment, one CO(3)(2-) anion, one full and two half 1,4-bis(imidazol-1-ylmethyl)benzene (bix) ligands, one half-molecule of which is uncoordinated, and five uncoordinated water molecules. One of the coordinated bix ligands and the uncoordinated bix molecule are situated about centers of symmetry, located at the centers of the benzene rings. The coordinated bix ligands link the copper(II) ions into a [Cu(bix)(1.5)](n) molecular ladder. These molecular ladders do not form interpenetrated ladders but are arranged in an ABAB parallel terrace, i.e. with the ladders arranged one above another, with sequence A translated with respect to B by 8 A. To best of our knowledge, this arrangement has not been observed in any of the molecular ladder frameworks synthesized to date. The coordination environment of the Cu(II) atom is completed by two O atoms of the CO(3)(2-) anion. The framework is further strengthened by extensive O-H...O and O-H...N hydrogen bonds involving the water molecules, the O atoms of the CO(3)(2-) anion and the N atoms of the bix ligands. This study describes the first example of a molecular ladder coordination polymer based on bix and therefore demonstrates further the usefulness of bix as a versatile multidentate ligand for constructing coordination polymers with interesting architectures.

One Dimensional Coordination Polymer of Zn(II) for Developing Multifunctional Nanoparticles.

PubMed

Agarwal, Rashmi A

2017-10-16

A variety of nanoparticles (NPs) including Ag, Au, Pd, Cr and mixed Cu/Fe have been synthesized in a non-activated (without solvent removal) one dimensional coordination polymer (CP) of Zn(II) via two different mechanisms, acid formation and redox activity of the framework. Main driving force to grow these NPs within the cavities of CP is the presence of free oxygens of one of the monodentate carboxylate groups of BDC ligand. These free oxygens act as anchoring sites for the metal ions of the metal precursors. Chemical and physical characteristics of the NPs within the framework have been evaluated by the high resolution transmission electron microscopic (HRTEM) images. Excluding Ag(0) and Pd(0) other NPs are present as combinations of their elemental as well as oxide forms (Au/Au 2 O 3 , Cr/Cr 2 O 3 /CrO 2 and Cu/Cu 2 O, Fe/FeO). Synthesized Ag NPs within the framework show remarkable antibacterial efficacy at extremely low concentrations. Ag, Au and Cu/Fe NPs show ferromagnetic properties within the framework at room temperature. This polymer has potential to sequester highly toxic Cr(VI) to non toxic Cr(0), Cr(III) and Cr(IV) species.

Developing multifunctional nanoparticles in a 1-D coordination polymer of Cd(II)

NASA Astrophysics Data System (ADS)

Agarwal, Rashmi A.; Gupta, Neeraj K.

2017-11-01

A simple synthesis for the integration of different nanoparticles (NPs) including Ag, Au, Pd, Cr and mixed (Cu/Fe), has been demonstrated within the nanopores of a non-activated one dimensional porous coordination polymer (PCP) of Cd(II) due to its high flexible structure. There are two different mechanisms (acid formation (HCl/HNO3) and redox activity of the framework) elucidated by electron paramagnetic resonance (EPR). Presence of -NO2 groups of the ligand act as anchoring sites for metal ions of metal precursors leading to NPs growth within the PCP explained by FTIR. High resolution transmission electron microscopy (HRTEM) images provided insight of the chemical and physical characteristics of the NPs within the framework. Ag/AgO NPs exhibit excellent antibacterial properties at extremely low concentrations. The polymer shows potential for sequestration and reduction of hexavalent Cr (highly toxic) to elemental, trivalent and tetravalent Cr (non toxic). This framework is also an excellent template for fabrication and dry storage of nanoparticles synthesized by mixed metal precursors. Ferromagnetic properties have been shown by Ag and Au NPs integrated frameworks while Cu/Fe@Cd-PCP behaves as a paramagnet material at room temperature.

Polymer-ionic liquid ternary systems for Li-battery electrolytes: Molecular dynamics studies of LiTFSI in a EMIm-TFSI and PEO blend

NASA Astrophysics Data System (ADS)

Costa, Luciano T.; Sun, Bing; Jeschull, Fabian; Brandell, Daniel

2015-07-01

This paper presents atomistic molecular dynamics simulation studies of lithium bis(trifluoromethane)sulfonylimide (LiTFSI) in a blend of 1-ethyl-3-methylimidazolium (EMIm)-TFSI and poly(ethylene oxide) (PEO), which is a promising electrolyte material for Li- and Li-ion batteries. Simulations of 100 ns were performed for temperatures between 303 K and 423 K, for a Li:ether oxygen ratio of 1:16, and for PEO chains with 26 EO repeating units. Li+ coordination and transportation were studied in the ternary electrolyte system, i.e., PEO16LiTFSIṡ1.0 EMImTFSI, by applying three different force field models and are here compared to relevant simulation and experimental data. The force fields generated significantly different results, where a scaled charge model displayed the most reasonable comparisons with previous work and overall consistency. It is generally seen that the Li cations are primarily coordinated to polymer chains and less coupled to TFSI anion. The addition of EMImTFSI in the electrolyte system enhances Li diffusion, associated to the enhanced TFSI dynamics observed when increasing the overall TFSI anion concentration in the polymer matrix.

Polymer-ionic liquid ternary systems for Li-battery electrolytes: Molecular dynamics studies of LiTFSI in a EMIm-TFSI and PEO blend.

PubMed

Costa, Luciano T; Sun, Bing; Jeschull, Fabian; Brandell, Daniel

2015-07-14

This paper presents atomistic molecular dynamics simulation studies of lithium bis(trifluoromethane)sulfonylimide (LiTFSI) in a blend of 1-ethyl-3-methylimidazolium (EMIm)-TFSI and poly(ethylene oxide) (PEO), which is a promising electrolyte material for Li- and Li-ion batteries. Simulations of 100 ns were performed for temperatures between 303 K and 423 K, for a Li:ether oxygen ratio of 1:16, and for PEO chains with 26 EO repeating units. Li(+) coordination and transportation were studied in the ternary electrolyte system, i.e., PEO16LiTFSI⋅1.0 EMImTFSI, by applying three different force field models and are here compared to relevant simulation and experimental data. The force fields generated significantly different results, where a scaled charge model displayed the most reasonable comparisons with previous work and overall consistency. It is generally seen that the Li cations are primarily coordinated to polymer chains and less coupled to TFSI anion. The addition of EMImTFSI in the electrolyte system enhances Li diffusion, associated to the enhanced TFSI dynamics observed when increasing the overall TFSI anion concentration in the polymer matrix.

Polymer-ionic liquid ternary systems for Li-battery electrolytes: Molecular dynamics studies of LiTFSI in a EMIm-TFSI and PEO blend

DOE Office of Scientific and Technical Information (OSTI.GOV)

Costa, Luciano T., E-mail: ltcosta@id.uff.br; Sun, Bing; Jeschull, Fabian

2015-07-14

This paper presents atomistic molecular dynamics simulation studies of lithium bis(trifluoromethane)sulfonylimide (LiTFSI) in a blend of 1-ethyl-3-methylimidazolium (EMIm)-TFSI and poly(ethylene oxide) (PEO), which is a promising electrolyte material for Li- and Li-ion batteries. Simulations of 100 ns were performed for temperatures between 303 K and 423 K, for a Li:ether oxygen ratio of 1:16, and for PEO chains with 26 EO repeating units. Li{sup +} coordination and transportation were studied in the ternary electrolyte system, i.e., PEO{sub 16}LiTFSI⋅1.0 EMImTFSI, by applying three different force field models and are here compared to relevant simulation and experimental data. The force fields generatedmore » significantly different results, where a scaled charge model displayed the most reasonable comparisons with previous work and overall consistency. It is generally seen that the Li cations are primarily coordinated to polymer chains and less coupled to TFSI anion. The addition of EMImTFSI in the electrolyte system enhances Li diffusion, associated to the enhanced TFSI dynamics observed when increasing the overall TFSI anion concentration in the polymer matrix.« less

A set of alkali and alkaline-earth coordination polymers based on the ligand 2-(1H-benzotriazol-1-yl) acetic acid: Effects the radius of metal ions on structures and properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Jin-Hua; Tang, Gui-Mei, E-mail: meiguit@163.com; Qin, Ting-Xiao

2014-11-15

Four new metal coordination complexes, namely, [Na(BTA)]{sub n} (1), [K{sub 2}(BTA){sub 2}(μ{sub 2}-H{sub 2}O)]{sub n} (2), and [M(BTA){sub 2}(H{sub 2}O){sub 2}]{sub n} (M=Ca(II) and Sr(II) for 3 and 4, respectively) [BTA=2-(1H-benzotriazol-1-yl) acetic anion], have been obtained under hydrothermal condition, by reacting the different alkali and alkaline-earth metal hydroxides with HBTA. Complexes 1–4 were structurally characterized by X-ray single-crystal diffraction, EA, IR, PXRD, and thermogravimetry analysis (TGA). These complexes display low-dimensional features displaying various two-dimensional (2D) and one-dimensional (1D) coordination motifs. Complex 1 displays a 2D layer with the thickness of 1.5 nm and possesses a topologic structure of a 11more » nodal net with Schläfli symbol of (3{sup 18}). Complex 2 also shows a thick 2D sheet and its topologic structure is a 9 nodes with Schläfli symbol of (3{sup 11}×4{sup 2}). Complexes 3 and 4 possess a 1D linear chain and further stack via hydrogen bonding interactions to generate a three-dimensional supramolecular architecture. These results suggest that both the coordination preferences of the metal ions and the versatile nature of this flexible ligand play a critical role in the final structures. The luminescent spectra show strong emission intensities in complexes 1–4, which display violet photoluminescence. Additionally, ferroelectric, dielectric and nonlinear optic (NLO) second-harmonic generation (SHG) properties of 2 are discussed in detail. - Graphical abstract: A set of alkali and alkaline-earth metal coordination polymers were hydrothermally synthesized by 2-(1H-benzotriazol-1-yl)acetic acid, displaying interesting topologic motifs from two-dimension to one-dimension and specific physical properties. - Highlights: • Alkali and alkaline-earth metal coordination polymers have been obtained. • The ligand 2-(1H-benzotriazol-1-yl)acetic acid has been adopted. • The two-dimensional and one-dimensional structures have been observed. • The properties of second harmonic generation and ferroelectricity for complex 2.« less

1D hetero-bimetallic regularly alternated 4f-3d coordination polymers based on N-oxide-4,4'-bipyridine (bipyMO) as a linker: photoluminescence and magnetic properties.

PubMed

Armelao, Lidia; Belli Dell'Amico, Daniela; Bottaro, Gregorio; Bellucci, Luca; Labella, Luca; Marchetti, Fabio; Mattei, Carlo Andrea; Mian, Federica; Pineider, Francesco; Poneti, Giordano; Samaritani, Simona

2018-06-13

Heterotopic divergent ligand N-oxide-4,4'-bipyridine (bipyMO) has been herein exploited for the preparation of hetero-bimetallic coordination polymers where Ln(hfac)3 and M(hfac)2 nodes regularly alternate (Hhfac = 1,1,1,5,5,5-hexafluoro-2,4-pentanedione), bipyMO being able to selectively use its two potential coordination sites to discriminate the metal ions. The synthesis of three coordination polymers, [Ln(hfac)3M(hfac)2(bipyMO)2]n (Ln = Eu, M = Zn, 1; Ln = Eu, M = Cu, 2, Ln = Dy, M = Co, 3), was carried out by reacting the appropriate [M(hfac)2(bipyMO)]n and [Ln(hfac)3] precursors in toluene in the presence of a given stoichiometric amount of bipyMO. The products were characterized by elemental analysis, X-ray powder diffraction, and FTIR spectroscopy. Single crystal X-ray diffraction studies carried out on 2 showed that it was formed by chains containing the hexa-coordinated 3d metal (Cu(hfac)2[N]2) and the octa-coordinated lanthanide (Eu(hfac)3[O]2) nodes, where [N] and [O] stand for the donor atom of the bridging divergent ligand. The X-ray powder diffraction patterns of the three compounds and the comparison of their cell constant values allowed establishing that the derivatives were isotypic. Photoluminescence (PL) studies on microcrystalline sample powders evidenced a bright red emission for 1 with an absolute PL quantum yield of 0.24. The sensitized emission of Eu3+ can be excited in a wide wavelength range, from UV to visible, up to ≈450 nm. Conversely, europium emissions are not detectable in 2 due to the presence of Cu(hfac)2(bipyMO) moieties whose strong absorption overlaps Eu3+ transitions. Magnetic measurements conducted on 3 revealed the presence of a weak ferromagnetic interaction below 2.1 K. An ac susceptibility study highlighted a slow relaxation of the magnetization of 3 with an applied static magnetic field of 0.1 T, which could be equally fitted with a Orbach-direct or a Raman-direct mechanism. No relaxation dynamics was detected without the application of a static magnetic field.

Luminescent zinc and cadmium complexes incorporating 1,3,5-benzenetricarboxylate and a protonated kinked organodiimine: From a hydrogen-bonded layer motif to thermally robust two-dimensional coordination polymers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Braverman, Maxwell A.; Supkowski, Ronald M.; LaDuca, Robert L.

2007-06-15

Hydrothermal treatment of zinc chloride, 1,3,5-benzenetricarboxylic acid (H{sub 3}BTC), and 4,4'-dipyridylamine (dpa) afforded two different complexes depending on reaction conditions, which were characterized by single-crystal X-ray diffraction, infrared spectroscopy, and elemental analysis. Under acidic conditions, a discrete neutral molecular species with formulation [Zn(HBTC){sub 2}(Hdpa){sub 2}] (1) was isolated, which aggregates into two-dimensional hydrogen-bonded layers. Under more basic conditions, the two-dimensional layered coordination polymer [Zn(BTC)(Hdpa)] (2) is obtained, which manifests covalent linkage of [Zn(BTC)(Hdpa)] serpentine chain motifs into 3-connected undulating 4.8{sup 2} topology 2-D layers. Both 1 and 2 possess tetrahedral coordination at Zn. Use of cadmium nitrate in the synthesismore » resulted in [Cd(BTC)(H{sub 2}O)(Hdpa)] (3), which displays a similar layer topology as 2 but with significant adjustments imparted by octahedral coordination at Cd. In all cases, supramolecular hydrogen bonding promoted by Hdpa ligands provide an important assistive structure-directing role. All materials display blue luminescence upon excitation with ultraviolet light, ascribed to intraligand transitions. Crystallographic data: 1: monoclinic, C2/c, a=25.389(6) A, b=9.811(2) A, c=17.309(4) A, and {beta}=128.957(3){sup o}, 2: monoclinic, P2{sub 1}/c, a=13.212(17)c, b=17.15(2) A, c=7.506(10) A, and {beta}=93.71(2){sup o}, and 3: monoclinic, C2/c, a=14.241(6) A, b=15.218(6) A, c=17.976(7) A, and {beta}=109.330(6){sup o}. - Graphical abstract: Hydrothermal synthesis has afforded a family of luminescent complexes based on divalent d {sup 10} cations with 1,3,5-benzenetricarboxylate (BTC) and 4,4'-dipyridylamine (dpa) ligands. [Zn(HBTC){sub 2}(Hdpa){sub 2}] (1) is a discrete neutral molecular species. [Zn(BTC)(Hdpa)] (2, pictured) and [Cd(BTC)(H{sub 2}O)(Hdpa)] (3) are 2-D coordination polymers with different morphologies depending on coordination geometry at the metal. All three materials exhibit blue-violet luminescence on exposure to ultraviolet radiation.« less

A symmetric, triply interlaced 3-D anionic MOF that exhibits both magnetic order and SMM behaviour.

PubMed

Campo, J; Falvello, L R; Forcén-Vázquez, E; Sáenz de Pipaón, C; Palacio, F; Tomás, M

2016-11-14

A newly prepared 3-D polymer of cobalt citrate cubanes bridged by high-spin Co(ii) centres displays both single-molecule magnet (SMM) behaviour and magnetic ordering. Triple interpenetration of the 3-D diamondoid polymers yields a crystalline solid with channels that host cations and free water molecules, with the SMM behaviour of the Co 4 O 4 cores preserved. The octahedrally coordinated Co(ii) bridges are implicated in the onset of magnetic order at an experimentally accessible temperature.

Water stability of microporous coordination polymers and the adsorption of pharmaceuticals from water.

PubMed

Cychosz, Katie A; Matzger, Adam J

2010-11-16

The stability of a variety of microporous coordination polymers (MCPs) to water-containing solutions was studied using powder X-ray diffraction. It was determined that the stability of the MCP is related to the metal cluster present in the structure with trinuclear chromium clusters more stable than copper paddlewheel clusters which are more stable than basic zinc acetate clusters. Zn(2-methylimidizolate)(2) was found to be more water stable than zinc MCPs with carboxylate linkers; however, extended exposure to water led to decomposition of all zinc-based MCPs. Matériaux de l'Institut Lavoisier (MIL)-100 was also found to be completely water stable and was used to adsorb the pharmaceuticals furosemide and sulfasalazine from water with large uptakes achievable at low concentrations, indicating that the adsorption of wastewater contaminants may be a feasible application for these materials.

(ZrO 2) 0.85( REO 1.5) 0.15 ( RE=Sc, Y) solid solutions prepared via three Pechini-type gel routes: 1—gel formation and calcination behaviors

NASA Astrophysics Data System (ADS)

Zhang, Yawen; Li, Ang; Yan, Zhengguang; Xu, Gang; Liao, Chunsheng; Yan, Chunhua

2003-02-01

(ZrO2)0.85(REO1.5)0.15 (RE=Sc, Y) nanoparticles with pure cubic fluorite structure have been synthesized by three Pechini-type gel routes, viz. poly(vinyl alcohol) containing-process (route I), poly(ethylene glycol) and formic acid-containing process (route II), and in situ polymerizable complex method (route III). The coordination modes between metal ions and polymers in the gels are shown to be highly correlative with the synthesis route used. The gels prepared by route III have the strongest coordination throughout their network and therefore the best chemical homogeneity. The altered variety of polymer and cross-linking within the gels adopted by these three routes has made the as-synthesized samples show appreciable differences in thermal behavior, powder reactivity and nanoparticle properties.

Two new coordination polymers with flexible alicyclic carboxylate and bipyridyl co-ligands bearing trinuclear [Ni3(COO)6] SBUs: Synthesis, crystal structures, and magnetic properties

NASA Astrophysics Data System (ADS)

Zhu, Xian-Dong; Li, Yong; Gao, Jian-Gang; Wang, Fen-Hua; Li, Qing-Hai; Yang, Hong-Xun; Chen, Lei

2017-02-01

Two new coordination polymers generally formulated as [Ni3(Hchda)2(chda)2(bpy)2(H2O)2]n (1) and [Ni3(Hchda)2(chda)2(bpp)2(H2O)2]n (2) [H2chda = 1,1'-cyclohexanediacetic acid, bpy = 4,4'-bipyridine and bpp = 1,3-bis(4-pyridyl)propane], have been successfully assembled through mixed-ligands synthetic strategy with flexible alicyclic carboxylate and bipyridyl ligands. There structures feature trinuclear nickel secondary building units connected via the bridging bipyridyl spacers to form two-dimensional (4,4) grid layer. The nature of the different N-donor auxiliary ligands leads to the discrepancy in supramolecular structure of the two compounds. Magnetic studies indicate the ferromagnetic intra-complex magnetic interaction in the molecule for 1 and 2.

Two double and triple interpenetrated Cd(II) and Zn(II) coordination polymers based on mixed O- and N-donor ligands: Syntheses, crystal structures and luminescent properties

NASA Astrophysics Data System (ADS)

Zhang, Li; Li, Xiaohui; Zhang, Yan

2016-01-01

Two interpenetrated 3D coordination polymers, namely [Cd2(tdc)2(bpp) (DMA)]n (1) and [Zn2(tdc)2(bib)2]n·2n(DMA) (2) (H2tdc = 2,5-thiophenedicarboxylic acid, bpp = 1,3-di(4-pyridyl)propane, bib = 1, 4-bis(imidazolyl)butane, DMA = N,N-dimethylacetamide), have been solvothermally synthesized by the self-assembly of flexible N-donor and dicarboxylate ligands. Single crystal X-ray diffraction analyses revealed that compound 1 features a 2-fold interpenetrated 3D framework based on dinuclear [Cd2(COO)3] subunits and can be simplified into a 6-connected pcu topology, and compound 2 features a 3-fold interpenetrated 3D framework with 4-connected dia topology. Moreover, the thermal stabilities and luminescent properties of these two compounds were also investigated.

Structural optimization of interpenetrated pillared-layer coordination polymers for ethylene/ethane separation.

PubMed

Kishida, Keisuke; Horike, Satoshi; Watanabe, Yoshihiro; Tahara, Mina; Inubushi, Yasutaka; Kitagawa, Susumu

2014-06-01

With the goal of achieving effective ethylene/ethane separation, we evaluated the gas sorption properties of four pillared-layer-type porous coordination polymers with double interpenetration, [Zn2(tp)2(bpy)]n (1), [Zn2(fm)2(bpe)]n (2), [Zn2(fm)2(bpa)]n (3), and [Zn2(fm)2(bpy)]n (4) (tp = terephthalate, bpy = 4,4'-bipyridyl, fm = fumarate, bpe = 1,2-di(4-pyridyl)ethylene and bpa = 1,2-di(4-pyridyl)ethane). It was found that 4, which contains the narrowest pores of all of these compounds, exhibited ethylene-selective sorption profiles. The ethylene selectivity of 4 was estimated to be 4.6 at 298 K based on breakthrough experiments using ethylene/ethane gas mixtures. In addition, 4 exhibited a good regeneration ability compared with a conventional porous material. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hydrothermal syntheses, crystal structures, and photophysical properties of two coordination polymers with mixed ligands

NASA Astrophysics Data System (ADS)

Yan, Li; Liu, Chun-Ling

2017-10-01

Two novel metal-organic coordination polymers [Cd(ipdt)(m-BDC)·3H2O]n (1) and [Pb(mip)2(NTC) ·2H2O]n (2) [ipdt = 2,6-Dimethoxy-4-(1H-1,3,7,8-tetraaza-cyclopenta[l]phenanthren-2-yl)-phenol, mip = 2-(3-methoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline, m-BDC = isophthalic acid, NTC = nicotinic acid] have been synthesized by hydrothermal reactions and characterized by elemental analysis, thermogravimetric (TG) analysis, infrared spectrum (IR) and single-crystal X-ray diffraction. Single-crystal X-ray diffraction reveals that 1 exhibits two-dimensional (2D) layer architecture, and 2 shows 1D chain architecture. TG analysis shows clear courses of weight loss, which corresponds to the decomposition of different ligands. The luminescent properties for the ligand ipdt, mip and complexes 1-2 are also discussed in detail, which should be acted as potential luminescent material.

Substituent-induced effects on dimensionality in cadmium isophthalate coordination polymers containing 3-pyridylisonicotinamide

NASA Astrophysics Data System (ADS)

O'Donovan, Megan E.; Wudkewych, Megan J.; LaDuca, Robert L.

2015-08-01

Hydrothermal treatment of cadmium nitrate, a 5-substituted isophthalic acid, and 3-pyridylisonicotinamide (3-pina) resulted in three coordination polymers whose dimensionality depended critically on the nature of the aromatic ring substituent. These three new phases were characterized by single crystal X-ray diffraction. {[Cd(hip)(3-pina)(H2O)2]·2H2O}n (1, hip = 5-hydroxyisophthalate) and {[Cd(meoip)(3-pina)(H2O)2]·H2O}n (2, meoip = 5-methoxyisophthalate) both manifest simple 1-D chain structures with pendant 3-pina ligands. [Cd(mip)(3-pina)]n (3, mip = 5-methylisophthalate) possesses [Cd(mip)]n 1-D chains featuring {Cd2(OCO)2} dimeric units, linked by tethering 3-pina ligands into a non-interpenetrated 3-D 6-connected 41263 pcu network. Luminescent behavior in all cases is attributed to intra-ligand molecular orbital transitions.

High-performance supercapacitors of Cu-based porous coordination polymer nanowires and the derived porous CuO nanotubes.

PubMed

Wu, Meng-Ke; Zhou, Jiao-Jiao; Yi, Fei-Yan; Chen, Chen; Li, Yan-Li; Li, Qin; Tao, Kai; Han, Lei

2017-12-12

Electrode materials for supercapacitors with one-dimensional porous nanostructures, such as nanowires and nanotubes, are very attractive for high-efficiency storage of electrochemical energy. Herein, ultralong Cu-based porous coordination polymer nanowires (copper-l-aspartic acid) were used as the electrode material for supercapacitors, for the first time. The as-prepared material exhibits a high specific capacitance of 367 F g -1 at 0.6 A g -1 and excellent cycling stability (94% retention over 1000 cycles). Moreover, porous CuO nanotubes were successfully fabricated by the thermal decomposition of this nanowire precursor. The CuO nanotube exhibits good electrochemical performance with high rate capacity (77% retention at 12.5 A g -1 ) and long-term stability (96% retention over 1000 cycles). The strategy developed here for the synthesis of porous nanowires and nanotubes can be extended to the construction of other electrode materials for more efficient energy storage.

Synthesis and characterization of a multifunctional inorganic-organic hybrid mixed-valence copper(I/II) coordination polymer: {[CuCN][Cu(isonic)2]}n

NASA Astrophysics Data System (ADS)

Liu, Dong-Sheng; Chen, Wen-Tong; Ye, Guang-Ming; Zhang, Jing; Sui, Yan

2017-12-01

A new multifunctional mixed-valence copper(I/II) coordination polymer, {[CuCN][Cu(isonic)2]}n(1) (Hisonic = isonicotinic acid), was synthesized by treating isonicotinic acid and 5-amino-tetrazolate (Hatz = 5-amino-tetrazolate) with copper(II) salts under hydrothermal conditions, and characterized by elemental analysis, infrared spectroscopy, and single crystal X-ray diffraction, respectively. The X-ray diffraction analysis reveals that compound exhibit noncentrosymmetric polar packing arrangement. It is three-dimensional (3D) framework with (3,5)-connected 'seh-3' topological network constructed from metal organic framework {[Cu(isonic)2]}n and the inorganic linear chain{Cu(CN)}n subunits. A remarkable feature of 1 is the rhombic open channels that are occupied by a linear chain of {Cu(CN)}n. Impressively compound 1 displays not only a second harmonic generation (SHG) response, but also a ferroelectric behavior and magnetic properties.

Coordination Polymers of 5-Alkoxy Isophthalic Acids

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCormick, Laura J.; Morris, Samuel A.; Slawin, Alexandra M. Z.

The topology of coordination polymers containing 5-alkoxy isophthalic acids and first row transition metals was found to be dependent on the combination of solvent system used and length of the alkyl chain. Four different framework types were thus identified: Phase A, M 6(ROip) 5(OH) 2(H 2O) 4·xH 2O (M = Co and R = Et, Pr, or nBu, or M = Zn and R = Et); Phase B,M 2(ROip) 2(H 2O) (M = Co or Zn and R = Et, Pr, nBu, or iBu, or M = Mn and R = nBu or iBu); Phase C, Zn 3(EtOip) 2(OH) 2;more » and Phase D, Zn 2(EtOip) 2(H 2O) 3. Preliminary screening of the NO storage and release capabilities of the Co-containing materials is also reported.« less

Sonochemical synthesis and characterization of a novel hetro-binuclear metal organic nano polymer based on picolinic acid ligand

NASA Astrophysics Data System (ADS)

Hayati, Payam; Souri, Bagher; Rezvani, Ali Reza; Morsali, Ali; Gutierrez, Angel

2017-12-01

Nanoparticles of one new lead and K coordination polymer (CP), {[Pb6(pyc)6(N3)7K].½H2O}n (1) Hpyc = picolinic acid ligand, has been synthesized by use of a sonochemical process and characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), Fourier transform infrared spectroscopy (FTIR) spectroscopy and elemental analyses. The single crystal X-ray data of compound 1 imply that the Pb ion is seven coordinated. The thermal stability of compound 1 has been studied by thermogravimetric (TG) and differential scanning calorimetry (DSC). The role of temperature, reaction time and ultrasound irradiation power on the size and morphfology of the nano-structured compound obtained from 1, have been investigated. Results indicate that an increase of temperature and sonication power and a decrease in time reaction led to a decrease of particle size.

Coordination Polymers of 5-Alkoxy Isophthalic Acids

DOE PAGES

McCormick, Laura J.; Morris, Samuel A.; Slawin, Alexandra M. Z.; ...

2016-08-23

The topology of coordination polymers containing 5-alkoxy isophthalic acids and first row transition metals was found to be dependent on the combination of solvent system used and length of the alkyl chain. Four different framework types were thus identified: Phase A, M 6(ROip) 5(OH) 2(H 2O) 4·xH 2O (M = Co and R = Et, Pr, or nBu, or M = Zn and R = Et); Phase B,M 2(ROip) 2(H 2O) (M = Co or Zn and R = Et, Pr, nBu, or iBu, or M = Mn and R = nBu or iBu); Phase C, Zn 3(EtOip) 2(OH) 2;more » and Phase D, Zn 2(EtOip) 2(H 2O) 3. Preliminary screening of the NO storage and release capabilities of the Co-containing materials is also reported.« less

Solvent Dependent Disorder in M 2(BzOip) 2(H 2O)·Solvate (M = Co or Zn)

DOE PAGES

McCormick, Laura; Morris, Samuel A.; Teat, Simon J.; ...

2017-12-24

Coordination polymers derived from 5-benzyloxy isophthalic acid (H 2BzOip) are rare, with only three reported that do not contain additional bridging ligands, of which two M 2(BzOip) 2(H 2O) (M = Co and Zn) are isomorphous. It was hoped that by varying the solvent system in a reaction between H 2BzOip and M(OAc) 2 (M = Co and Zn), from water to a water/alcohol mixture, coordination polymers of different topology could be formed. Instead, two polymorphs of the existing M 2(BzOip) 2(H 2O) (M = Co and Zn) were isolated from aqueous methanol and aqueous ethanol, in which a smallmore » number of guest solvent molecules are present in the crystals. These guest water molecules disrupt the hexaphenyl embrace motif, leading to varying degrees of disorder of the benzyl groups.« less

Crystal structure and magnetic properties of a unique 3D coordination polymer constructed from flexible aliphatic tricarballylic acid ligands featuring linear trimeric Manganese(II)-based, metal carboxylate chains

NASA Astrophysics Data System (ADS)

Zou, Hua-Hong; Zhang, Shu-Hua; Zeng, Ming-Hua; Zhou, Yan-Ling; Liang, Hong

2008-08-01

A novel linear trimeric-based, Mn(II)-carboxylate chain well separated by long-linking flexible aliphatic tricarballylic acid ligands in a 3D coordination polymer [Mn 3(C 6H 5O 6) 2(H 2O) 4] n ( 1, C 6H 5O 6dbnd CH (COO -)(CH 2COO -) 2, TCA) exhibits low-dimensional antiferromagnetic order at 3.0 K. Such magnetic behavior is arises from the alternate Antiferro-Antiferro-Antiferro' ( J1J1J2) repeating interactions sequence, based on the nature of the binding modes of Mn(II)-carboxylate chain and the effect of interchains arrangement of 1. The reported carboxylate-bridged metal chain systems display a new structurally authenticated example of linear homometallic spin arranged antiferromagnet among metal carboxylates.

Exploring 3D non-interpenetrated metal-organic framework with malonate-bridged Co(II) coordination polymer: structural elucidation and theoretical study

NASA Astrophysics Data System (ADS)

Hossain, Anowar; Mandal, Tripti; Mitra, Monojit; Manna, Prankrishna; Bauzá, Antonio; Frontera, Antonio; Seth, Saikat Kumar; Mukhopadhyay, Subrata

2017-12-01

A Co(II)-based coordination polymer with tetranuclear cobalt(II)-malonate cluster has been easily generated by aqueous medium self-assembly from Cobalt(II) chloride hexahydrate and malonic acid. The structure exhibits a non-interpenetrating, highly undulating two-dimensional (2D) bi-layer network with (4,4) topology. The crystal structure is composed of infinite interdigitated 2D metal-organic bi-layers which extended to an intricate 3D framework through the interbilayer hydrogen bonds. We have studied energetically by means of Density Functional Theory (DFT) calculations the H-bonding interactions that connect the 2D metal-organic bi-layers. The finite theoretical models have been used to compute conventional O‒H•••O and unconventional C‒H•••O interactions which plays a key role to build 3D architecture.

Solvent Dependent Disorder in M 2(BzOip) 2(H 2O)·Solvate (M = Co or Zn)

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCormick, Laura; Morris, Samuel A.; Teat, Simon J.

Coordination polymers derived from 5-benzyloxy isophthalic acid (H 2BzOip) are rare, with only three reported that do not contain additional bridging ligands, of which two M 2(BzOip) 2(H 2O) (M = Co and Zn) are isomorphous. It was hoped that by varying the solvent system in a reaction between H 2BzOip and M(OAc) 2 (M = Co and Zn), from water to a water/alcohol mixture, coordination polymers of different topology could be formed. Instead, two polymorphs of the existing M 2(BzOip) 2(H 2O) (M = Co and Zn) were isolated from aqueous methanol and aqueous ethanol, in which a smallmore » number of guest solvent molecules are present in the crystals. These guest water molecules disrupt the hexaphenyl embrace motif, leading to varying degrees of disorder of the benzyl groups.« less

Structure and Properties of Azobenzene Thin-Films

NASA Astrophysics Data System (ADS)

Allen, R. A.

1987-09-01

Available from UMI in association with The British Library. A number of monomer and polymer materials, all containing the azobenzene group, have been deposited as Langmuir-Blodgett (LB) multilayers and their structures and physical properties studied. LB films of two monomeric materials exhibited liquid crystal phase changes that were investigated by optical microscopy and X-ray diffraction. Multilayers built up from one of the materials exhibited a phase change upon aging and this demonstrated that the LB technique had produced a structure that was not the equilibrium state. A monomer material possessing a fluorocarbon chain was found to initially deposit as an LB film in a Z-type manner, but changed to Y-type deposition with increasing multilayer thickness. A correlation was observed between this behaviour and the surface potential changes that were brought about when deposition took place on an aluminium substrate. The feasibility of building up alternating multilayers of monomer and polymer materials was demonstrated. Combining these two classes of material in the same LB film may confer on it the mechanical durability of the polymers and the highly ordered structure and potentially interesting physical properties of the monomer. The structures developed here may prove to have high second harmonic generation capabilities. Polymer materials were built up into relatively thick Y-type LB multilayers and studied by X-ray diffraction. Only poorly defined layered structures were found. Polymer materials were also cast into thin films from the melt and from solution. One of the compounds developed a high degree of anisotropy in its structure after exposure to linearly polarised white light. A birefringence of up to Deltan = 0.21 was measured. In contrast, LB films formed from the same material could not be ordered in the same manner and this appeared to result from the very close packing that takes place in such structures.

Lanthanide coordination polymers based on multi-donor ligand containing pyridine and phthalate moieties: Structures, luminescence and magnetic properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feng, Xun; Liu, Lang; College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022

2013-10-15

A new family of five lanthanide-organic coordination polymers incorporating multi-functional N-hetrocyclic dicarboxylate ligand, namely, [Ln{sub 2}(Hdpp){sub 2}(dpp){sub 2}]{sub n}Ln=Pr(1), Eu(2), Gd(3), Dy(4), Er(5) (H{sub 2}dpp=1-(3, 4-dicarboxyphenyl) pyridin-4-ol) have been fabricated successfully through solvothermal reaction of 1-(3,4-dicarboxyphenyl)-4-hydroxypyridin-1-ium chloride with trivalent lanthanide salts, and have been characterized systematically. The complexes 1–5 are isomorphous and isostructural. They all feature three dimensional (3D) frameworks based on the interconnection of 1D double chains composed of the binuclear moiety [Ln{sub 2}(Hdpp){sub 2}]{sup 4+} basic carboxylate as secondary building unit (SBU). The results of magnetic analysis shows the same bridging fashion of carboxylic group in this casemore » results in the different magnetic properties occurring within lanthanide polymers. Moreover, the Eu(III) and Dy(III) complexes display characteristic luminescence emission in the visible regions. - Graphical abstract: A new family of lanthanide-organic frameworks incorporating multi-donor twisted ligand has been fabricated successfully, and has been characterized systematically. The complexes 1–5 are isostructural, and all feather three dimensional (3D) frameworks based on the interconnection of 1D double stride chains composed of the binuclear moiety [Ln{sub 2}(Hdpp){sub 2}]{sup 2+} basic carboxylate as secondary building unit (SBU). Display Omitted - Highlights: • New family of lanthanide–organic coordination polymers incorporating multifunctional N-hetrocyclic dicarboxylate ligand has been fabricated. • They have been characterized systematically. • They all feather three dimensional frameworks based on the binuclear moiety of [Ln{sub 2}(Hdpp){sub 2}]{sup 2+}. • The Eu(III) and Dy(III) analogues exhibit intense photoluminescence.« less

Milestoning with coarse memory

NASA Astrophysics Data System (ADS)

Hawk, Alexander T.

2013-04-01

Milestoning is a method used to calculate the kinetics of molecular processes occurring on timescales inaccessible to traditional molecular dynamics (MD) simulations. In the method, the phase space of the system is partitioned by milestones (hypersurfaces), trajectories are initialized on each milestone, and short MD simulations are performed to calculate transitions between neighboring milestones. Long trajectories of the system are then reconstructed with a semi-Markov process from the observed statistics of transition. The procedure is typically justified by the assumption that trajectories lose memory between crossing successive milestones. Here we present Milestoning with Coarse Memory (MCM), a generalization of Milestoning that relaxes the memory loss assumption of conventional Milestoning. In the method, milestones are defined and sample transitions are calculated in the standard Milestoning way. Then, after it is clear where trajectories sample milestones, the milestones are broken up into distinct neighborhoods (clusters), and each sample transition is associated with two clusters: the cluster containing the coordinates the trajectory was initialized in, and the cluster (on the terminal milestone) containing trajectory's final coordinates. Long trajectories of the system are then reconstructed with a semi-Markov process in an extended state space built from milestone and cluster indices. To test the method, we apply it to a process that is particularly ill suited for Milestoning: the dynamics of a polymer confined to a narrow cylinder. We show that Milestoning calculations of both the mean first passage time and the mean transit time of reversal—which occurs when the end-to-end vector reverses direction—are significantly improved when MCM is applied. Finally, we note the overhead of performing MCM on top of conventional Milestoning is negligible.

The assembly of two isomorphous coordination compounds based on 1,4-cyclohexanedicarboxylic acid and 2,4-diamino-6-phenyl-1,3,5-triazine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Xue-Fei; Wang, Xiao; Lun, Hui-Jie

The compounds [Co(e,a-cis-1,4-chdc)(phdat)]{sub n} (1) and [Cd(e,a-cis-1,4-chdc)(phdat)]{sub n} (2) have been synthesized under hydrothermal method by using 1,4-cyclohexanedicarboxylic acid (1,4-H{sub 2}chdc), 2,4-diamino-6-phenyl-1,3,5-triazine (phdat) as well as CoCl{sub 2}·6H{sub 2}O, CdCl{sub 2}·2.5H{sub 2}O respectively and characterized by IR spectra, X-ray single-crystal diffraction, powder X-ray single-crystal diffraction (PXRD), elemental analyses and thermogravimetric analyses (TGA). The results show the compounds 1 and 2 are isomorphous and exhibit paddle-wheel dinuclear Co{sub 2}(CO{sub 2}){sub 4}/Cd{sub 2}(CO{sub 2}){sub 4} units, which are further connected to 1D chain structures by μ{sub 4}:η{sup 1}:η{sup 1}:η{sup 1}:η{sup 1} 1,4-chdc{sup 2–} ligands and extended into a 3D structures via differentmore » hydrogen bonding and π…π stacking interactions. Furthermore, compound 1 exhibits antiferromagnetic behavior and compound 2 displays luminescent behavior at solid state. - Graphical abstract: Two isomorphous coordination compounds 1–2 have been synthesized and characterized by XRD, IR spectra and TGA etc. Compound 1 and 2 display antiferromagnetic behavior and luminescent behavior respectively. - Highlights: • Two novel polymers based on 1,4-cyclohexanedicarboxylic acid have been synthesized. • Compounds 1 and 2 feather 1D chain structure built up from paddle-wheel SBUs. • The magnetism of 2 is investigated. • The electrochemical property and luminescent property of 1 are investigated.« less

I. the Synthesis and Coordination Chemistry of Novel 6Pi-Electron Ligands. II. Improvement of Student Writing Skills in General Chemistry Lab Reports through the Use of Calibrated Peer Review

ERIC Educational Resources Information Center

William, Wilson Ngambeki

2011-01-01

Abstract I. The goal of this study was to synthesize and characterize a set of coordination complexes containing 6pi-cationic ligands. These compounds could be extremely useful as catalysts for the polymerization of olefins that are widely used in the synthetic polymer industry. The original strategy was to synthesize the 6pi-cationic ligands…

Intralanthanide Separation on Layered Titanium(IV) Organophosphate Materials via a Selective Transmetalation Process.

PubMed

Zhang, Wenzhong; Hietala, Sami; Khriachtchev, Leonid; Hatanpää, Timo; Doshi, Bhairavi; Koivula, Risto

2018-06-21

The lanthanides (Ln) are an essential part of many advanced technologies. Our societal transformation toward renewable energy drives their ever-growing demand. The similar chemical properties of the Ln pose fundamental difficulties in separating them from each other, yet high purity elements are crucial for specific applications. Here, we propose an intralanthanide separation method utilizing a group of titanium(IV) butyl phosphate coordination polymers as solid-phase extractants. These materials are characterized, and they contain layered structures directed by the hydrophobic interaction of the alkyl chains. The selective Ln uptake results from the transmetalation reaction (framework metal cation exchange), where the titanium(IV) serves as sacrificial coordination centers. The "tetrad effect" is observed from a dilute Ln 3+ mixture. However, smaller Ln 3+ ions are preferentially extracted in competitive binary separation models between adjacent Ln pairs. The intralanthanide ion-exchange selectivity arises synergistically from the coordination and steric strain preferences, both of which follow the reversed Ln contraction order. A one-step aqueous separation of neodymium (Nd) and dysprosium (Dy) is quantitatively achievable by simply controlling the solution pH in a batch mode, translating into a separation factor of greater than 2000 and 99.1% molar purity of Dy in the solid phase. Coordination polymers provide a versatile platform for further exploring selective Ln separation processes via the transmetalation process.

Two three-dimensional coordination polymers of lead(II) with iminodiacetate and naphthalene-dicarboxylate anions: Synthesis, characterization and luminescence behavior

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hazari, Debdoot; Jana, Swapan Kumar; Fleck, Michel

2014-11-15

Two lead(II) compounds [Pb{sub 3}(idiac){sub 3}(phen){sub 2}(H{sub 2}O)]·2(H{sub 2}O) (1) and [Pb(ndc)]{sub n} (2), where H{sub 2}idiac=iminodiacetic acid, phen=1,10-phenanthroline and H{sub 2}ndc=naphthalene-2,6-dicarboxylic acid, have been synthesized and structurally characterized. Single crystal X-ray diffraction analysis showed that compound 1 is a discrete trinuclear complex (of two-fold symmetry) which evolves to a supramolecular 3D network via π–π interactions, while in compound 2 the naphthalene dicarboxylate anion act as a linker to form a three dimensional architecture, where the anion adopts a bis-(bidentate bridging) coordination mode connecting four Pb(II) centers. The photoluminescence property of the two complexes has been studied. - graphical abstract:more » Two new topologically different 1D coordination polymers formed by Pb{sub 4} clusters have been synthesized and characterized by x-ray analysis. The luminescence and thermal properties have been studied. - Highlights: • 1 is a trinuclear complex of Pb(II) growing to 3D network via weak interactions. • In 1, layers of (4,4) rhomboidal topology are identified. • In 2, the ndc anion adopts interesting bis-(bidentate bridging) coordination. • In 2, network is reinforced by C–H…π-ring interactions between the ndc rings.« less

Near-infrared light stimuli-responsive synergistic therapy nanoplatforms based on the coordination of tellurium-containing block polymer and cisplatin for cancer treatment.

PubMed

Li, Feng; Li, Tianyu; Cao, Wei; Wang, Lu; Xu, Huaping

2017-07-01

Cisplatin (CDDP) has received worldwide approval for clinical use in the past decades. However, its development in cancer chemotherapy was overshadowed by severe side effects and drug resistance. Herein, we developed a CDDP drug delivery system with high encapsulation efficiency and near-infrared light stimuli-responsive drug release properties based on the coordination of novel tellurium-containing block polymer (PEG-PUTe-PEG) and CDDP. The nanocarriers made from PEG-PUTe-PEG were loaded with CDDP and indocyanine green (ICG) simultaneously. The coordination chemistry between CDDP and tellurium guaranteed the nanocarrier a high stability in plasma and prolonged circulation time in vivo by reducing possible penetration of water molecule into the nanoparticles. Under the stimuli of a near-infrared laser, an amount of ROS can be generated by irradiation of ICG. The tellurium is easily oxidized by ROS because of the low electronegativity of tellurium. The CDDP could be rapidly released from the nanocarriers along with the oxidation of the tellurium at the tumor sites as the oxidized tellurium will weaken the coordination interaction with CDDP. In addition, the encapsulated ICG played a synergistic antitumor effect through photothermal effect with mild laser irradiation. The integrated strategy achieved higher antitumor efficacy and showed minimal side effects compared with the CDDP alone. Copyright © 2017 Elsevier Ltd. All rights reserved.

Syntheses, structures and magnetic properties of four coordination polymers based on nitrobenzene dicarboxylate and various N-donor coligands

NASA Astrophysics Data System (ADS)

Li, Gui-Lian; Yin, Wei-Dong; Liu, Guang-Zhen; Ma, Lu-Fang; Wang, Li-Ya

2014-12-01

Four new coordination polymers {[Ni(4-Nbdc)(bpa)(H2O)]}n (1), {[Co(4-Nbdc)(bpp) (H2O)]}n (2), {[Ni(4-Nbdc)(bpp)(H2O)]·H2O}n (3), and {[Mn2(3-Nbdc)2(bib)3]·2H2O}n (4) (4-Nbdc=4-nitrobenzene-1,2-dicarboxylate, 3-Nbdc=3-nitrobenzene-1,2-dicarboxylate, bpa=1,2-bi(4-pyridyl)ethane, bpp=1,3-bis(4-pyridyl)propane, and bib=1,4-bis(1-imidazoly)benzene), were synthesized by hydrothermal reactions, and characterized by single-crystal X-ray diffractions, elemental analysis, FT-IR, PXRD, TGA and magnetic analysis. Complexes 1 and 2 display quasi-trapezoidal chain and brick-wall layer, and both of them contain metal-carboxylate binuclear units. Complexes 3 and 4 exhibit three-dimensional frameworks with the (66) dia topology and (44.610.8)(44.62) fsc topology, and both of them contain metal-carboxylate chains. The carboxyl groups with syn-anti coordination mode mediate effectively the weak ferromagnetic coupling interaction within Ni(II)-carboxylate binuclear in 1 (J=1.27 cm-1) and Ni(II)-carboxylate chain in 3 (J=1.44 cm-1), respectively, and the carboxyl groups with anti-anti coordination mode leads to the classic antiferromagnetic coupling interaction within Mn(II)-carboxylate chain in 4 (J=-0.77 cm-1).

Redox-active porous coordination polymers prepared by trinuclear heterometallic pivalate linking with the redox-active nickel(II) complex: synthesis, structure, magnetic and redox properties, and electrocatalytic activity in organic compound dehalogenation in heterogeneous medium.

PubMed

Lytvynenko, A S; Kolotilov, S V; Kiskin, M A; Cador, O; Golhen, S; Aleksandrov, G G; Mishura, A M; Titov, V E; Ouahab, L; Eremenko, I L; Novotortsev, V M

2014-05-19

Linking of the trinuclear pivalate fragment Fe2CoO(Piv)6 by the redox-active bridge Ni(L)2 (compound 1; LH is Schiff base from hydrazide of 4-pyridinecarboxylic acid and 2-pyridinecarbaldehyde, Piv(-) = pivalate) led to formation of a new porous coordination polymer (PCP) {Fe2CoO(Piv)6}{Ni(L)2}1.5 (2). X-ray structures of 1 and 2 were determined. A crystal lattice of compound 2 is built from stacked 2D layers; the Ni(L)2 units can be considered as bridges, which bind two Fe2CoO(Piv)6 units. In desolvated form, 2 possesses a porous crystal lattice (SBET = 50 m(2) g(-1), VDR = 0.017 cm(3) g(-1) estimated from N2 sorption at 78 K). At 298 K, 2 absorbed a significant quantity of methanol (up to 0.3 cm(3) g(-1)) and chloroform. Temperature dependence of molar magnetic susceptibility of 2 could be fitted as superposition of χMT of Fe2CoO(Piv)6 and Ni(L)2 units, possible interactions between them were taken into account using molecular field model. In turn, magnetic properties of the Fe2CoO(Piv)6 unit were fitted using two models, one of which directly took into account a spin-orbit coupling of Co(II), and in the second model the spin-orbit coupling of Co(II) was approximated as zero-field splitting. Electrochemical and electrocatalytic properties of 2 were studied by cyclic voltammetry in suspension and compared with electrochemical and electrocatalytic properties of a soluble analogue 1. A catalytic effect was determined by analysis of the catalytic current dependency on concentrations of the substrate. Compound 1 possessed electrocatalytic activity in organic halide dehalogenation, and such activity was preserved for the Ni(L)2 units, incorporated into the framework of 2. In addition, a new property occurred in the case of 2: the catalytic activity of PCP depended on its sorption capacity with respect to the substrate. In contrast to homogeneous catalysts, usage of solid PCPs may allow selectivity due to porous structure and simplify separation of product.

Step-by-step thermal transformations of a new porous coordination polymer [(H{sub 2}O){sub 5}CuBa(Me{sub 2}mal){sub 2}]{sub n} (Me{sub 2}mal{sup 2-}=dimethylmalonate): Thermal degradation to barium cuprate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zauzolkova, Natalya, E-mail: zauzolkova@igic.ras.ru; Dobrokhotova, Zhanna; Lermontov, Anatoly

The reactions of CuSO{sub 4}{center_dot}5H{sub 2}O, dimethylmalonic acid and Ba(OH){sub 2}{center_dot}H{sub 2}O (Cu: H{sub 2}Me{sub 2}mal: Ba=1: 2: 2) in aqueous and aqueous-ethanol solutions (H{sub 2}O: EtOH=1: 1) resulted in formation of 3D-porous coordination polymers [(H{sub 2}O){sub 3}({mu}-H{sub 2}O){sub 2}CuBa({mu}{sub 3}-Me{sub 2}mal)(Me{sub 2}mal)]{sub n} (1) and [({mu}-H{sub 2}O)CuBa({mu}{sub 3}-Me{sub 2}mal)({mu}{sub 4}-Me{sub 2}mal)]{sub n} (2), respectively. It has been shown that compound 2 was an intermediate in the thermal degradation of compound 1. Thorough studies of solid-state thermolysis of 1 and 2 allowed to detect formation of coordination polymer [CuBa({mu}{sub 4}-Me{sub 2}mal)({mu}{sub 5}-Me{sub 2}mal)]{sub n} (3), structure of which was determinedmore » by X-ray powder diffraction. It has been found that the channels in polymer 3 were accessible for guest molecules (MeOH). Theoretical estimation of methanol diffusion barrier was carried out. Complete solid-phase thermolysis of 1 and 2 leads to a mixture of BaCuO{sub 2}, BaCO{sub 3}, and CuO. Special conditions for obtaining of a crystalline phase of pure cubic BaCuO{sub 2} were determined. - Graphical abstract: Step-by-step transformation of new coordination polymer [(H{sub 2}O){sub 5}CuBa(Me{sub 2}mal){sub 2}]{sub n} to [(H{sub 2}O)CuBa(Me{sub 2}mal){sub 2}]{sub n} and [CuBa(Me{sub 2}mal){sub 2}]{sub n} were performed. Dehydration of initial compound leads to structural changes of 12-membered ring fragment. All compounds have porous structure. The final product of thermal decomposition is crystalline phase of individual cubic BaCuO{sub 2}. Highlights: Black-Right-Pointing-Pointer New 3D-polymers [(H{sub 2}O){sub 5}CuBa(Me{sub 2}mal){sub 2}]{sub n} and [(H{sub 2}O)CuBa(Me{sub 2}mal){sub 2}]{sub n} were synthesized. Black-Right-Pointing-Pointer Thermal analysis showed step-by-step transformations of [(H{sub 2}O){sub 5}CuBa(Me{sub 2}mal){sub 2}]{sub n}. Black-Right-Pointing-Pointer Crystalline phase of pure cubic BaCuO{sub 2} is the product solid-phase thermolysis.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yin, Wen-Yu; Zhuang, Guo-Yong; Huang, Zuo-Long

Three cadmium coordination polymers, [Cd(bismip)]{sub n} (1), {[Cd(bismip)(phen)]·H_2O}{sub n} (2) and {[Cd_2(bismip)_2(4,4′-bipy)]·2H_2O}{sub n} (3) (H{sub 2}bismip=5-(1H-benzoimidazol-2-ylsulfanylmethyl)-isophthalic acid, phen=1,10-phenanthroline, 4,4′-bipy=4,4′-bipyridine) have been prepared under solvothermal conditions. In 1, the [Cd{sub 4}(bismip){sub 3}] units are jointed by bismip ligands to afford a three-dimensional (3D) architecture. Complex 2 exhibits a 3D supramolecular framework based on the interconnection of 1D chains through hydrogen bonding interactions and π-π packing interactions. 3 is a two-fold interpenetrating 3D architecture with a (4·8{sup 2})(4{sup 2}·8{sup 4}) Schläfli symbol in which 2D layers are interlinked by 4,4′-bipy ligands. The diverse structures of compounds 1–3 indicate that the auxiliary ligandsmore » have significant effects on the final structures. The photoluminescent properties and photocatalytic properties of these coordination polymers in the solid state were also investigated. Remarkably, 3 shows the wide gap semiconductor nature and exhibit excellent photocatalytic performance. - Graphical abstract: Three cadmium coordination polymers with different architectures based on 5-(1H-benzoimidazol-2-ylsulfanylmethyl)-isophthalic acid have been prepared. Their photoluminescent properties were also investigated. - Highlights: • Three new Cd(II) Cps were synthesized based on H{sub 2}bismip. • Compounds 1 and 3 show 3D networks and 2 exhibits a 1D chain. • Compoud 3 exhibits good catalytic activity of methylene blue photodegradation.« less

Studies of the structural and magnetic properties of an unsymmetrical ligand 1,2,4-benzenetricarboxylic acid based chiral 3-D trinickel coordination polymer as an alkali base-influenced hydrothermal reaction product

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peng, Yi-Ru; Chien, Po-Hsiu; Chung, Huey-Ting

2014-04-01

The reaction of 1,2,4-benzenetricarboxylic acid (H{sub 3}btc), as a ligand, under pH-controlled hydrothermal conditions with nickel salts leads to the formation of a coordination polymer of (CsNi{sub 3}(OH)(H{sub 2}O){sub 3}[C{sub 6}H{sub 3}(CO{sub 2}){sub 3}]{sub 2}·3H{sub 2}O){sub n} (1). The subunit of compound 1 contains a hydroxide- and carboxylate-bridged trinickel clusters that are linked by an unsymmetrical organic carboxylate spacer to form a chiral three-dimensional anionic framework, in which cesium cations and guest water molecules are located in one-dimensional channels. The presence of a hydroxide ion serves both as a deprotonation agent and a cation source during the hydrothermal reaction, thusmore » permitting the extent of deprotonation of the unsymmetrical ligand H{sub 3}btc to be controlled, which is essential for the successful formation of compound 1. The magnetic properties of compound 1 were analyzed. Both dc and ac magnetic susceptibility as well as reduced magnetization measurements confirmed the spin-frustration nature of 1. - Graphical abstract: A chiral three-dimension MOF compound and its magnetic properties are described. - Highlights: • A new chiral three-dimension coordination polymer were made. • An un-symmetric bridging ligand was used. • Alkali metal ion Cs{sup +} was incorporated in the structure. • Magnetic properties were studied.« less

Two interpenetrating Cu{sup II}/Ni{sup II}-coordinated polymers based on an unsymmetrical bifunctional N/O-tectonic: Syntheses, structures and magnetic properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Yong-Liang; Department of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Comprehensive Utilization of Tailings Resources, Shang Luo University, Shang Luo 726000; Wu, Ya-Pan

2015-03-15

Two new interpenetrating Cu{sup II}/Ni{sup II} coordination polymers, based on a unsymmetrical bifunctional N/O-tectonic 3-(pyrid-4′-yl)-5-(4″-carbonylphenyl)-1,2,4-triazolyl (H{sub 2}pycz), ([Cu-(Hpycz){sub 2}]·2H{sub 2}O){sub n} (1) and ([Ni(Hpycz){sub 2}]·H{sub 2}O){sub n} (2), have been solvothermally synthesized and structure characterization. Single crystal X-ray analysis indicates that compound 1 shows 2-fold parallel interpenetrated 4{sup 4}-sql layers with the same handedness. The overall structure of 1 is achiral—in each layer of doubly interpenetrating nets, the two individual nets have the opposite handedness to the corresponding nets in the adjoining layers—while 2 features a rare 8-fold interpenetrating 6{sup 6}-dia network that belongs to class IIIa interpenetration. In addition,more » compounds 1 and 2 both show similar paramagnetic characteristic properties. - Graphical abstract: Two new Cu(II)/Ni(II) coordination polymers present 2D parallel 2-fold interpenetrated 4{sup 4}-sql layers and a rare 3D 8-fold interpenetrating 6{sup 6}-dia network. In addition, magnetic susceptibility measurements show similar paramagnetic characteristic for two complexes. - Highlights: • A new unsymmetrical bifunctional N/O-tectonic as 4-connected spacer. • A 2-fold parallel interpenetrated sql layer with the same handedness. • A rare 8-fold interpenetrating dia network (class IIIa)« less

Switching on fluorescence for selective visual recognition of naringenin and morin with a metal-organic coordination polymer of Zn(bix) [bix = 1,4-bis(imidazol-1-ylmethyl)benzene

NASA Astrophysics Data System (ADS)

Zhao, Xi Juan; Wang, Hui Juan; Liang, Li Jiao; Li, Yuan Fang

2013-02-01

Flavonoids such as naringenin and morin are ubiquitous in a wide range of foods isolated from plants, and have diverse effects on plants even on human health. Here, we establish a selective visual method for recognition of aringenin and morin based on the "switched on" fluorescence induced by a metal-organic coordination polymer of Zn(bix) [bix = 1,4-bis(imidazol-1-ylmethyl)benzene]. Owing to the coordination interaction of aringenin and morin with Zn(II) from the polymeric structure of Zn(bix), the conformational free rotation of naringenin and morin is restricted leading to relatively rigid structures. And as a consequence, the fluorescence is switched on. While luteolin and quercetin, holding a very similar structure with naringenin and morin, have no such fluorescence enhancement most likely owing to the 3'-hydroxy substitution in the B ring. Under 365 nm UV lamp light, we can visually recognize and discriminate naringenin and morin from them each other and luteolin as well as quercetin based on the colors of their emission. With this recognition system, the detection of naringenin and morin in human urine was made with satisfactory results.

Nanopatterning of Surfaces with Monometallic and Heterobimetallic 1D Coordination Polymers: A Molecular Tectonics Approach at the Solid/Liquid Interface.

PubMed

El Garah, Mohamed; Marets, Nicolas; Mauro, Matteo; Aliprandi, Alessandro; Bonacchi, Sara; De Cola, Luisa; Ciesielski, Artur; Bulach, Véronique; Hosseini, Mir Wais; Samorì, Paolo

2015-07-08

The self-assembly of multiple molecular components into complex supramolecular architectures is ubiquitous in nature and constitutes one of the most powerful strategies to fabricate multifunctional nanomaterials making use of the bottom-up approach. When spatial confinement in two dimensions on a solid substrate is employed, this approach can be exploited to generate periodically ordered structures from suitably designed molecular tectons. In this study we demonstrate that physisorbed directional periodic arrays of monometallic or heterobimetallic coordination polymers can be generated on a highly oriented pyrolitic graphite surface by combinations of a suitably designed directional organic tecton or metallatecton based on a porphyrin or nickel(II) metalloporphyrin backbone bearing both a pyridyl unit and a terpyridyl unit acting as coordinating sites for CoCl2. The periodic architectures were visualized at the solid/liquid interface with a submolecular resolution by scanning tunneling microscopy and corroborated by combined density functional and time-dependent density functional theory calculations. The capacity to nanopattern the surface for the first time with two distinct metallic centers exhibiting different electronic and optical properties is a key step toward the bottom-up construction of robust multicomponent and, thus, multifunctional molecular nanostructures and nanodevices.

White-emissive tandem-type hybrid organic/polymer diodes with (0.33, 0.33) chromaticity coordinates.

PubMed

Guo, Tzung-Fang; Wen, Ten-Chin; Huang, Yi-Shun; Lin, Ming-Wei; Tsou, Chuan-Cheng; Chung, Chia-Tin

2009-11-09

This study reports fabrication of white-emissive, tandem-type, hybrid organic/polymer light-emitting diodes (O/PLED). The tandem devices are made by stacking a blue-emissive OLED on a yellow-emissive phenyl-substituted poly(para-phenylene vinylene) copolymer-based PLED and applying an organic oxide/Al/molybdenum oxide (MoO(3)) complex structure as a connecting structure or charge-generation layer (CGL). The organic oxide/Al/MoO(3) CGL functions as an effective junction interface for the transport and injection of opposite charge carriers through the stacked configuration. The electroluminescence (EL) spectra of the tandem-type devices can be tuned by varying the intensity of the emission in each emissive component to yield the visible-range spectra from 400 to 750 nm, with Commission Internationale de l'Eclairage chromaticity coordinates of (0.33, 0.33) and a high color rendering capacity as used for illumination. The EL spectra also exhibit good color stability under various bias conditions. The tandem-type device of emission with chromaticity coordinates, (0.30, 0.31), has maximum brightness and luminous efficiency over 25,000 cd/m(2) and approximately 4.2 cd/A, respectively.

Application of a novel red-emitting cationic iridium(III) coordination polymer in warm white light-emitting diodes

NASA Astrophysics Data System (ADS)

Chen, Mingxian; Sun, Riyong; Ye, Yanchun; Tang, Huaijun; Dong, Xueyan; Yan, Jialun; Wang, Kaimin; Zhou, Qiang; Wang, Zhengliang

2018-02-01

A novel red-emitting cationic iridium(III) coordination polymer using 2-(9-(2-ethylhexyl)-9H-carbazol-3-yl)benzo[d]thiazole as main ligands, 4,4‧-bipyridine as bridging auxiliary ligands and Clˉ as anions was synthesized. It had high thermal stability with a thermal decomposition temperature (Td) of 345 °C and low thermal quenching with an activation energy (Ea) of 0.2760 eV, with the temperature increasing from 20 °C to 100 °C, its photoluminescent intensity decreased to 76.7%. It can be efficiently excited by blue light of GaN chips, the cold white light of GaN-based LEDs using only Y3Al5O12:Ce3+ (YAG:Ce, 7.0 wt% in silicone) as phosphors can become warmer when it was blended in. When blending concentrations were 0.1 wt% and 0.2 wt%, the cold white light became neutral white light, the correlated color temperature (CCT) decreased from 6157 K to 5240 K, then to 4043 K, the color rendering index (CRI) changed from 72.7 to 81.3, then to 78.6, the luminous efficiency (ηL) changed from 134.1 lm·w-1 to 61.9 lm·w-1, then to 46.3 lm·w-1, the Commission Internationale de L'Eclairage (CIE) chromaticity coordinates changed from (0.32, 0.33) to (0.34, 0.33), then to (0.38, 0.36). At 0.3 wt%, the light became warm white light, the corresponding CCT was 3475 K, CRI was 75.6, ηL was 36.9 lm·w-1, and CIE value was (0.41, 0.40). The results suggest the coordination polymer is a promising red-emitting phosphor candidate for neutral and warm white LEDs, especially for warm white LEDs.

Polymer matrix electroluminescent materials and devices

DOEpatents

Marrocco, III, Matthew L.; Motamedi, Farshad J [Claremont, CA; Abdelrazzaq, Feras Bashir [Covina, CA; Abdelrazzaq, legal representative, Bashir Twfiq

2012-06-26

Photoluminescent and electroluminescent compositions are provided which comprise a matrix comprising aromatic repeat units covalently coordinated to a phosphorescent or luminescent metal ion or metal ion complexes. Methods for producing such compositions, and the electroluminescent devices formed therefrom, are also disclosed.

A novel stereotactic frame for real PET-guided biopsies: A preclinical proof-of-concept.

PubMed

Cortes-Rodicio, J; Sanchez-Merino, G; Garcia-Fidalgo, M A; Tobalina-Larrea, I

2017-09-01

To design, build and test a stereotactic device that allows PET image-guided biopsies to be performed. An initial prototype consisting of four main pieces, one of which contains radioactive markers to make it visible in the PET images, was built using a 3D printer. Once the device is mounted, a spherical coordinate system is built with the entrance needle point in the skin as the origin of coordinates. Two in-house software programs, namely getCoord.ijm, which obtains the spherical coordinates of the tumour tissue to be biopsied, and getNeedle.ijm, which virtualizes the inner needle tip once the puncture has taken place, were written. This prototype was tested on an FDG-doped phantom to characterize both the accuracy of the system and the procedure time. Up to 11 complete biopsy procedures were conducted. The mean total procedure time was less than 20min, which is less than the procedure time of conventional standard CT-guided biopsies. The overall accuracy of the system was found to be 5.0±1.3mm, which outperforms the criterion used in routine clinical practice when targeting tumours with a diameter of 10mm. A stereotactic frame to conduct real PET image-guided biopsies has been designed and built. A proof-of-concept was performed to characterize the system. The procedure time and accuracy of the system were found to meet the current needs of physicians performing biopsies. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

A supramolecular Tröger's base derived coordination zinc polymer for fluorescent sensing of phenolic-nitroaromatic explosives in water.

PubMed

Shanmugaraju, Sankarasekaran; Dabadie, Charlyne; Byrne, Kevin; Savyasachi, Aramballi J; Umadevi, Deivasigamani; Schmitt, Wolfgang; Kitchen, Jonathan A; Gunnlaugsson, Thorfinnur

2017-02-01

A V-Shaped 4-amino-1,8-napthalimide derived tetracarboxylic acid linker ( L ; bis-[ N -(1,3-benzenedicarboxylic acid)]-9,18-methano-1,8-naphthalimide-[ b , f ][1,5]diazocine) comprising the Tröger's base (TB) structural motif was rationally designed and synthesised to access a nitrogen-rich fluorescent supramolecular coordination polymer. By adopting the straight forward precipitation method, a new luminescent nanoscale Zn(ii) coordination polymer ( TB-Zn-CP ) was synthesized in quantitative yield using Zn(OAc) 2 ·2H 2 O and tetraacid linker L (1 : 0.5) in DMF at room temperature. The phase-purity of as-synthesised TB-Zn-CP was confirmed by X-ray powder diffraction analysis, infra-red spectroscopy, and elemental analysis. Thermogravimetric analysis suggests that TB-Zn-CP is thermally stable up to 330 °C and the morphological features of TB-Zn-CP was analysed by SEM and AFM techniques. The N 2 adsorption isotherm of thermally activated TB-Zn-CP at 77 K revealed a type-II reversible adsorption isotherm and the calculated Brunauer-Emmett-Teller (BET) surface area was found to be 72 m 2 g -1 . Furthermore, TB-Zn-CP displayed an excellent CO 2 uptake capacity of 76 mg g -1 at 273 K and good adsorption selectivity for CO 2 over N 2 and H 2 . The aqueous suspension of as-synthesized TB-Zn-CP showed strong green fluorescence ( λ max = 520 nm) characteristics due to the internal-charge transfer (ICT) transition and was used as a fluorescent sensor for the discriminative sensing of nitroaromatic explosives. The aqueous suspension of TB-Zn-CP showed the largest quenching responses with high selectivity for phenolic-nitroaromatics (4-NP, 2,4-DNP and PA) even in the concurrent presence of other potentially competing nitroaromatic analytes. The fluorescence titration studies also provide evidence that TB-Zn-CP detects picric acid as low as the parts per billion (26.3 ppb) range. Furthermore, the observed fluorescence quenching responses of TB-Zn-CP towards picric acid were highly reversible. The highly selective fluorescence quenching responses including the reversible detection efficiency make the nanoscale coordination polymer TB-Zn-CP a potential material for the discriminative fluorescent sensing of nitroaromatic explosives.

Zn(II) coordination polymers with flexible V-shaped dicarboxylate ligand: Syntheses, helical structures and properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Lin; Liu, Chong-Bo, E-mail: cbliu@nchu.edu.cn; Yang, Gao-Shan

2015-11-15

Hydrothermal reactions of 2,2′-[hexafluoroisopropylidenebis(p-phenyleneoxy)]diacetic acid (H{sub 2}L) and zinc ions in the presence of N-donor ancillary ligands afford four novel coordination polymers, namely, [Zn{sub 2}(μ{sub 2}-OH)(μ{sub 4}-O){sub 0.5}(L)]·0.5H{sub 2}O (1), [Zn(L)(2,2′-bipy)(H{sub 2}O)] (2), [Zn{sub 3}(L){sub 3}(phen){sub 2}]·H{sub 2}O (3) and [Zn{sub 2}(L){sub 2}(4,4′-bipy)] (4) (2,2′-bipy=2,2′-bipyridine; 4,4′-bipy=4,4′-bipyridine; phen=1,10-phenanthroline). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Complex 1 shows a 3-D clover framework consisting of [Zn{sub 4}(µ{sub 4}-O)(µ{sub 2}-OH){sub 2}]{sup 4+} clusters, and exhibits a novel (3,8)-connected topological net with the Schläfli symbol of {3·4·5}{sub 2}{3"4·4"4·5"2·6"6·7"1"0·8"2}, andmore » contains double-stranded and two kinds of meso-helices. 2 displays a helical chain structure, which is further extended via hydrogen bonds into a 3-D supramolecular structure with meso-helix chains. 3 displays a 2-D {4"4·6"2} parallelogram structure, which is further extended via hydrogen bonds into a 3-D supramolecular structure with single-stranded helical chains. 4 shows a 2-D {4"4·6"2} square structure with left- and right-handed helical chains. Moreover, the luminescent properties of 1–4 have been investigated. - Graphical abstract: Four new Zn(II) coordination polymers with helical structures based on flexible V-shaped dicarboxylate ligand have been synthesized and structurally characterized. Photoluminescent properties have been investigated. - Highlights: • Four novel Zn(II) coordination polymers with V-shaped ligand were characterized. • Complexes 1–4 show diverse intriguing helical characters. • Fluorescence properties of complexes 1–4 were investigated.« less

Effect of hole injection layer/hole transport layer polymer and device structure on the properties of white OLED.

PubMed

Cho, Ho Young; Park, Eun Jung; Kim, Jin-Hoo; Park, Lee Soon

2008-10-01

Copolymers containing carbazole and aromatic amine unit were synthesized by using Pd-catalyzed polycondensation reaction. The polymers were characterized in terms of their molecular weight and thermal stability and their UV and PL properties in solution and film state. The band gap energy of the polymers was also determined by the UV absorption and HOMO energy level data. The polymers had high HOMO energy level of 5.19-5.25 eV and work function close to that of ITO. The polymers were thus tested as hole injection/transport layer in the white organic light emitting diodes (OLED) by using 4,4'-bis(2,2-diphenyl-ethen-1-yl)diphenyl (DPVBi) as blue emitting material and 5,6,11,12-tetraphenylnaphthacene (Rubrene) as orange emitting dopant. The synthesized polymer, poly bis[6-bromo-N-(2-ethylhexyl)-carbazole-3-yl] was found to be useful as hole injection layer/hole transport layer (HIL/HTL) multifunctional material with high luminance efficiency and stable white color coordinate in the wide range of applied voltage.

Towards seamlessly-integrated textile electronics: methods to coat fabrics and fibers with conducting polymers for electronic applications.

PubMed

Allison, Linden; Hoxie, Steven; Andrew, Trisha L

2017-06-29

Traditional textile materials can be transformed into functional electronic components upon being dyed or coated with films of intrinsically conducting polymers, such as poly(aniline), poly(pyrrole) and poly(3,4-ethylenedioxythiophene). A variety of textile electronic devices are built from the conductive fibers and fabrics thus obtained, including: physiochemical sensors, thermoelectric fibers/fabrics, heated garments, artificial muscles and textile supercapacitors. In all these cases, electrical performance and device ruggedness is determined by the morphology of the conducting polymer active layer on the fiber or fabric substrate. Tremendous variation in active layer morphology can be observed with different coating or dyeing conditions. Here, we summarize various methods used to create fiber- and fabric-based devices and highlight the influence of the coating method on active layer morphology and device stability.

Experimental simulation of internal short circuit in Li-ion and Li-ion-Polymer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cai, Wei; Wang, Hsin; Maleki, Hossein

A multi-parameter controlled pinch test was developed to study the occurrence of internal short circuits in Li-ion and Li-ion-polymer cells. By tuning the control parameters (i.e., cell voltage as well as pinching area, load, and speed), the pinch test can reproducibly create ~1 to 2 mm wide internal short between a cell jelly-roll s inner layer electrodes. This recreates conditions similar to those that may occur during service. Furthermore, the pinch test is used to determine thermal stability of two Li-ion-polymer cells of different designs built by the same manufacturer. The pinch test method can be used to help distinguishmore » cells with design features or characteristics that lower risk of potential thermal events created by internal short circuits.« less

Cantilevered multilevel LIGA devices and methods

DOEpatents

Morales, Alfredo Martin; Domeier, Linda A.

2002-01-01

In the formation of multilevel LIGA microstructures, a preformed sheet of photoresist material, such as polymethylmethacrylate (PMMA) is patterned by exposure through a mask to radiation, such as X-rays, and developed using a developer to remove the exposed photoresist material. A first microstructure is then formed by electroplating metal into the areas from which the photoresist has been removed. Additional levels of microstructure are added to the initial microstructure by covering the first microstructure with a conductive polymer, machining the conductive polymer layer to reveal the surface of the first microstructure, sealing the conductive polymer and surface of the first microstructure with a metal layer, and then forming the second level of structure on top of the first level structure. In such a manner, multiple layers of microstructure can be built up to allow complex cantilevered microstructures to be formed.

Blue Thermally Activated Delayed Fluorescence Polymers with Nonconjugated Backbone and Through-Space Charge Transfer Effect.

PubMed

Shao, Shiyang; Hu, Jun; Wang, Xingdong; Wang, Lixiang; Jing, Xiabin; Wang, Fosong

2017-12-13

We demonstrate novel molecular design for thermally activated delayed fluorescence (TADF) polymers based on a nonconjugated polyethylene backbone with through-space charge transfer effect between pendant electron donor (D) and acceptor (A) units. Different from conventional conjugated D-A polymers with through-bond charge transfer effect, the nonconjugated architecture avoids direct conjugation between D and A units, enabling blue emission. Meanwhile, spatial π-π interaction between the physically separated D and A units results in both small singlet-triplet energy splitting (0.019 eV) and high photoluminescence quantum yield (up to 60% in film state). The resulting polymer with 5 mol % acceptor unit gives efficient blue electroluminescence with Commission Internationale de l'Eclairage coordinates of (0.176, 0.269), together with a high external quantum efficiency of 12.1% and low efficiency roll-off of 4.9% (at 1000 cd m -2 ), which represents the first example of blue TADF nonconjugated polymer.

Design of Polymer-Grafted Particles for Biocompatability

NASA Astrophysics Data System (ADS)

Trombly, David; Ganesan, Venkat

2009-03-01

Drug designers often coat drug particles with grafted polymers in order to introduce a net repulsion between the particles and blood proteins. This net repulsion results from the energy cost of compressing grafted chains on approach of proteins. It thus overcomes the Van Der Waals attraction between drug and protein which would otherwise cause particle-protein agglomeration and ultimately thrombosis. This study proposes to develop a fundamental understanding of the role of different features in controlling the efficacy of the grafted layers. We address this issue by developing a framework to predict the interactions between a polymer-coated spherical particle and a bare spherical particle. In order to fully capture the two-sphere system, a numerical solution of polymer mean field theory is used in a bispherical coordinate system. Results for protein-particle interaction energies for different design parameters will be presented. For biological applications, polyethylene glycol is often used as the grafted polymer. The unique properties of this molecule will be accounted for using the n-cluster model.

A lead (II) 3D coordination polymer based on a marine cyclic peptide motif.

PubMed

Chakraborty, Subrata; Tyagi, Pooja; Tai, Dar-Fu; Lee, Gene-Hsiang; Peng, Shie-Ming

2013-04-26

The crystal structure of a naturally occurring cyclic tetrapeptide cyclo(Gly-L-Ser-L-Pro-L-Glu) [cyclo(GSPE)] was obtained. The conformation of synthesized cyclo(GSPE) fixes the coordination to lead ion in a 1:1 ratio. This cyclo(GSPE)-Pb complex was constructed as an asymmetric 3D network in the crystalline state. The polymerization of a heavy metal ion with a rigid asymmetric cyclic tetrapeptide represents the first example of a new class of macrocyclic complexes.

Engineering the bio-nano interface using a multi-functional polymer coating

NASA Astrophysics Data System (ADS)

Wang, Wentao

Interfacing inorganic nanoparticles with biological systems to develop a variety of novel imaging, sensing and diagnostic tools has generated great interest and much activity over the past two decades. However, the effectiveness of this approach hinges on the ability to prepare water dispersible nanoparticles, with compact size and long term colloidal stability in biological environments, and the development of controlled conjugation to various biomolecules. The primary focus of this dissertation is the design and synthesis, characterization and use of a series of new multidentate and multifunctional coordinating polymers as ligands that render various inorganic nanocrystals water soluble, In Chapter 1 we introduce the basic physical properties of quantum dots (QDs), gold nanocrystals and magnetic nanocrystals along with brief description of their syntheses. We then provide an overview of surface functionalization strategies and recent progress in the ligand chemistry, followed by highlights of a few conjugation approaches applied to nanoparticles in biology. We then discuss modulation of the optical and spectroscopic properties of QDs via energy and charge transfer interactions. We conclude by presenting a few related examples on the incorporation of QD-conjugates into sensor design and intracellular imaging. In Chapter 2, we report the design of a series of multifunctional polymers as ligands for surface engineering of QDs and facilitating their use in bioconjugation. First, we introduce a novel PEGylated polymer that combines the synergies of metal-chelation promoted by lipoic acid and imidazole groups, as effective coating for the surface functionalization of QDs; one of the goals was to address the problems associated with thiol oxidation and weak imidazole affinity. Second, to minimize the hydrodynamic radius of the QDs without sacrificing aqueous solubility, a set of polymer ligands appended with zwitterion and imidazole motifs have been synthesized applied for the surface engineering of QDs. Third, modulation of the nanoparticle's interaction with biological systems requires access to an effective conjugation of these materials with bioactive targets in a controlled manner. To fulfill this goal, we have developed several zwitterion-based multifunctional ligands presenting tunable functional groups, including carboxyl, amine, azide and biotin. This has allowed conjugation of the QDs to biomolecules via bio-orthogonal coupling chemistries, including (1) amine-isothiocyanate reaction; (2) biotin-streptavidin self-assembly; (3) copper-free click chemistry. The resulted QD-bioconjugates have been tested in sensor design and for cell imaging. We also find that the efficiency of polyhistidine-mediated metal coordination is not only determined by the ligand lateral extension but also greatly influenced by the nature of metal coordination on the QDs. In Chapter 3, we have applied the various multi-coordinating and multi-reactive polymers, in particular, those presenting lipoic acid and PEG for the functionalization of gold nanoparticles and nanorods. Gold nanocrystals coated with this polymer exhibit excellent long-term colloidal stability over a broad range of conditions, and furthermore prevent the formation of protein corona. This was verified using dynamic light scattering measurements combined with agarose gel electrophoresis. The diffusion properties of polymer-coated nanocrystals were further characterized using dynamic light scattering; this has yielded valuable information on the nature of the interparticle interactions in biological media. In Chapter 4, an additional set of modular ligands were synthesized and applied for the surface modification of iron oxide nanoparticles. These ligands feature several dopamines for tight binding on iron oxide nanoparticle surface, a short PEG for water solubility and reactive groups (amine, carboxyl, azide and thiol) for bioconjugation. Nanoparticles functionalized with these polymers show extended stability in biologically relevant conditions and little to no cytotoxicity. We demonstrate that covalent attachment of dye enables producing luminescent probe for cell imaging. (Abstract shortened by ProQuest.).

The coordination chemistry of group 15 element ligand complexes--a developing area.

PubMed

Scheer, Manfred

2008-09-07

A survey of the contemporary challenges of the field of unsubstituted group 15 element ligand complexes (excluding N) is given. The focus of the article is on the coordination chemistry behaviour of such E(n) ligand complexes. This field is subdivided into two areas of reactivity: E(n) ligand complexes with (i) noncoordinated Lewis-acidic cations and (ii) Lewis-acidic coordination compounds containing at least one permanently coordinating ligand. In the latter case, insoluble 1D and 2D polymers respectively are obtained; however, under special conditions soluble, spherical, fullerene-like giant molecules are formed. These nano-sized molecules are up to 2.4 nm in diameter and are able to encapsulate small molecules in their holes. In contrast, the first-mentioned field uses weakly coordinating anions to obtain readily soluble di- and polycationic products. These show depolymerisation tendencies in solution under the formation of oligomer-monomer equilibria and thus reveal dynamic supramolecular aggregation processes.

Poly[diaqua­tris­(μ4-1,3-phenyl­enediacetato)­dineodymium(III)

PubMed Central

Gao, Zhu-Qing; Lv, Dong-Yu; Li, Hong-Ji; Gu, Jin-Zhong

2011-01-01

In the title coordination polymer, [Nd2(C10H8O4)3(H2O)2]n, each of the two NdIII ions is nine-coordinated by eight O atoms from six different 2,2′-(m-phenyl­ene)diacetate (pda) bivalent anions and by one O atom from a water mol­ecule, forming a distorted tricapped trigonal–prismatic coordination geometry. Eight NdIII ions and 12 pda ligands form a large [Nd8(pda)12] ring, and four NdIII ions and six pda ligands form a small [Nd4(pda)6] ring. These rings are further connected by the coordination inter­actions of pda ligands and NdIII, generating a three-dimensional supra­molecular framework. PMID:21522305

Dispersion and interaction of graphene oxide in amorphous and semi-crystalline nano-composites: a PALS study

NASA Astrophysics Data System (ADS)

Maurer, Frans H. J.; Arza, Carlos R.

2015-06-01

The influence of dispersion and interaction of Graphene Oxide (GO) in semicrystalline Polyhydroxy butyrate (PHB) and glassy amorphous Poly(tBP-oda) is explored by Positron Annihilation Lifetime Spectroscopy (PALS). The ortho-Positronium lifetimes which represent the main free volume hole size of both polymers are mainly affected by the large differences in internal stresses built up by the shrinkage of the polymers during their preparation, restricted by the platelet structure of GO. The ortho-Positronium intensities, which represent the ortho-Positronium formation probabilities, suggest a strong dependency of on the dispersion of the nano-particles and their aspect ratio.

Smiles2Monomers: a link between chemical and biological structures for polymers.

PubMed

Dufresne, Yoann; Noé, Laurent; Leclère, Valérie; Pupin, Maude

2015-01-01

The monomeric composition of polymers is powerful for structure comparison and synthetic biology, among others. Many databases give access to the atomic structure of compounds but the monomeric structure of polymers is often lacking. We have designed a smart algorithm, implemented in the tool Smiles2Monomers (s2m), to infer efficiently and accurately the monomeric structure of a polymer from its chemical structure. Our strategy is divided into two steps: first, monomers are mapped on the atomic structure by an efficient subgraph-isomorphism algorithm ; second, the best tiling is computed so that non-overlapping monomers cover all the structure of the target polymer. The mapping is based on a Markovian index built by a dynamic programming algorithm. The index enables s2m to search quickly all the given monomers on a target polymer. After, a greedy algorithm combines the mapped monomers into a consistent monomeric structure. Finally, a local branch and cut algorithm refines the structure. We tested this method on two manually annotated databases of polymers and reconstructed the structures de novo with a sensitivity over 90 %. The average computation time per polymer is 2 s. s2m automatically creates de novo monomeric annotations for polymers, efficiently in terms of time computation and sensitivity. s2m allowed us to detect annotation errors in the tested databases and to easily find the accurate structures. So, s2m could be integrated into the curation process of databases of small compounds to verify the current entries and accelerate the annotation of new polymers. The full method can be downloaded or accessed via a website for peptide-like polymers at http://bioinfo.lifl.fr/norine/smiles2monomers.jsp.Graphical abstract:.

Compensation of Horizontal Gravity Disturbances for High Precision Inertial Navigation

PubMed Central

Cao, Juliang; Wu, Meiping; Lian, Junxiang; Cai, Shaokun; Wang, Lin

2018-01-01

Horizontal gravity disturbances are an important factor that affects the accuracy of inertial navigation systems in long-duration ship navigation. In this paper, from the perspective of the coordinate system and vector calculation, the effects of horizontal gravity disturbance on the initial alignment and navigation calculation are simultaneously analyzed. Horizontal gravity disturbances cause the navigation coordinate frame built in initial alignment to not be consistent with the navigation coordinate frame in which the navigation calculation is implemented. The mismatching of coordinate frame violates the vector calculation law, which will have an adverse effect on the precision of the inertial navigation system. To address this issue, two compensation methods suitable for two different navigation coordinate frames are proposed, one of the methods implements the compensation in velocity calculation, and the other does the compensation in attitude calculation. Finally, simulations and ship navigation experiments confirm the effectiveness of the proposed methods. PMID:29562653

A junction-tree based learning algorithm to optimize network wide traffic control: A coordinated multi-agent framework

DOE PAGES

Zhu, Feng; Aziz, H. M. Abdul; Qian, Xinwu; ...

2015-01-31

Our study develops a novel reinforcement learning algorithm for the challenging coordinated signal control problem. Traffic signals are modeled as intelligent agents interacting with the stochastic traffic environment. The model is built on the framework of coordinated reinforcement learning. The Junction Tree Algorithm (JTA) based reinforcement learning is proposed to obtain an exact inference of the best joint actions for all the coordinated intersections. Moreover, the algorithm is implemented and tested with a network containing 18 signalized intersections in VISSIM. Finally, our results show that the JTA based algorithm outperforms independent learning (Q-learning), real-time adaptive learning, and fixed timing plansmore » in terms of average delay, number of stops, and vehicular emissions at the network level.« less

Hyperspectral imaging of polymer banknotes for building and analysis of spectral library

NASA Astrophysics Data System (ADS)

Lim, Hoong-Ta; Murukeshan, Vadakke Matham

2017-11-01

The use of counterfeit banknotes increases crime rates and cripples the economy. New countermeasures are required to stop counterfeiters who use advancing technologies with criminal intent. Many countries started adopting polymer banknotes to replace paper notes, as polymer notes are more durable and have better quality. The research on authenticating such banknotes is of much interest to the forensic investigators. Hyperspectral imaging can be employed to build a spectral library of polymer notes, which can then be used for classification to authenticate these notes. This is however not widely reported and has become a research interest in forensic identification. This paper focuses on the use of hyperspectral imaging on polymer notes to build spectral libraries, using a pushbroom hyperspectral imager which has been previously reported. As an initial study, a spectral library will be built from three arbitrarily chosen regions of interest of five circulated genuine polymer notes. Principal component analysis is used for dimension reduction and to convert the information in the spectral library to principal components. A 99% confidence ellipse is formed around the cluster of principal component scores of each class and then used as classification criteria. The potential of the adopted methodology is demonstrated by the classification of the imaged regions as training samples.

Rapid Self-healing Nanocomposite Hydrogel with Tunable Dynamic Mechanics

NASA Astrophysics Data System (ADS)

Li, Qiaochu; Mishra, Sumeet; Chapman, Brian; Chen, Pangkuan; Tracy, Joseph; Holten-Andersen, Niels

The macroscopic healing rate and efficiency in self-repairing hydrogel materials are largely determined by the dissociation dynamics of their polymer network, which is hardly achieved in a controllable manner. Inspired by mussel's adhesion chemistry, we developed a novel approach to assemble inorganic nanoparticles and catechol-decorated PEG polymer into a hydrogel network. When utilized as reversible polymer-particle crosslinks, catechol-metal coordination bonds yield a unique gel network with dynamic mechanics controlled directly by interfacial crosslink structure. Taking advantage of this structure-property relationship at polymer-particle interfaces, we designed a hierarchically structured hybrid gel with two distinct relaxation timescales. By tuning the relative contribution of the two relaxation modes, we are able to finely control the gel's dynamic mechanical behavior from a viscoelastic fluid to a stiff solid, yet preserving its rapid self-healing property without the need for external stimuli.

Molecular weaving via surface-templated epitaxy of crystalline coordination networks.

NASA Astrophysics Data System (ADS)

Wang, Zhengbang; Błaszczyk, Alfred; Fuhr, Olaf; Heissler, Stefan; Wöll, Christof; Mayor, Marcel

2017-02-01

One of the dream reactions in polymer chemistry is the bottom-up, self-assembled synthesis of polymer fabrics, with interwoven, one-dimensional fibres of monomolecular thickness forming planar pieces of textiles. We have made a major step towards realizing this goal by assembling sophisticated, quadritopic linkers into surface-mounted metal-organic frameworks. By sandwiching these quadritopic linkers between sacrificial metal-organic framework thin films, we obtained multi-heteroepitaxial, crystalline systems. In a next step, Glaser-Hay coupling of triple bonds in the quadritopic linkers yields linear, interwoven polymer chains. X-ray diffraction studies revealed that this topochemical reaction leaves the MOF backbone completely intact. After removing the metal ions, the textile sheets can be transferred onto different supports and imaged using scanning electron microscopy and atomic-force microscopy. The individual polymer strands forming the two-dimensional textiles have lengths on the order of 200 nm, as evidenced by atomic-force microscopy images recorded from the disassembled textiles.

A study on optical properties of poly (ethylene oxide) based polymer electrolyte with different alkali metal iodides

NASA Astrophysics Data System (ADS)

Rao, B. Narasimha; Suvarna, R. Padma

2016-05-01

Polymer electrolytes were prepared by adding poly (ethylene glycol) dimethyl ether (PEGDME), TiO2 (nano filler), different alkali metal iodide salts RI (R+=Li+, Na+, K+, Rb+, Cs+) and I2 into Acetonitrile gelated with Poly (ethylene oxide) (PEO). Optical properties of poly (ethylene oxide) based polymer electrolytes were studied by FTIR, UV-Vis spectroscopic techniques. FTIR spectrum reveals that the alkali metal cations were coordinated to ether oxygen of PEO. The optical absorption studies were made in the wavelength range 200-800 nm. It is observed that the optical absorption increases with increase in the radius of alkali metal cation. The optical band gap for allowed direct transitions was evaluated using Urbach-edges method. The optical properties such as optical band gap, refractive index and extinction coefficient were determined. The studied polymer materials are useful for solar cells, super capacitors, fuel cells, gas sensors etc.

Mussel-inspired histidine-based transient network metal coordination hydrogels

PubMed Central

Fullenkamp, Dominic E.; He, Lihong; Barrett, Devin G.; Burghardt, Wesley R.; Messersmith, Phillip B.

2013-01-01

Transient network hydrogels cross-linked through histidine-divalent cation coordination bonds were studied by conventional rheologic methods using histidine-modified star poly(ethylene glycol) (PEG) polymers. These materials were inspired by the mussel, which is thought to use histidine-metal coordination bonds to impart self-healing properties in the mussel byssal thread. Hydrogel viscoelastic mechanical properties were studied as a function of metal, pH, concentration, and ionic strength. The equilibrium metal-binding constants were determined by dilute solution potentiometric titration of monofunctional histidine-modified methoxy-PEG and were found to be consistent with binding constants of small molecule analogs previously studied. pH-dependent speciation curves were then calculated using the equilibrium constants determined by potentiometric titration, providing insight into the pH dependence of histidine-metal ion coordination and guiding the design of metal coordination hydrogels. Gel relaxation dynamics were found to be uncorrelated with the equilibrium constants measured, but were correlated to the expected coordination bond dissociation rate constants. PMID:23441102

Computational Materials Research

NASA Technical Reports Server (NTRS)

Hinkley, Jeffrey A. (Editor); Gates, Thomas S. (Editor)

1996-01-01

Computational Materials aims to model and predict thermodynamic, mechanical, and transport properties of polymer matrix composites. This workshop, the second coordinated by NASA Langley, reports progress in measurements and modeling at a number of length scales: atomic, molecular, nano, and continuum. Assembled here are presentations on quantum calculations for force field development, molecular mechanics of interfaces, molecular weight effects on mechanical properties, molecular dynamics applied to poling of polymers for electrets, Monte Carlo simulation of aromatic thermoplastics, thermal pressure coefficients of liquids, ultrasonic elastic constants, group additivity predictions, bulk constitutive models, and viscoplasticity characterization.

Mechanical properties of metal-organic frameworks: An indentation study on epitaxial thin films

NASA Astrophysics Data System (ADS)

Bundschuh, S.; Kraft, O.; Arslan, H. K.; Gliemann, H.; Weidler, P. G.; Wöll, C.

2012-09-01

We have determined the hardness and Young's modulus of a highly porous metal-organic framework (MOF) using a standard nanoindentation technique. Despite the very low density of these films, 1.22 g cm-3, Young's modulus reaches values of almost 10 GPa for HKUST-1, demonstrating that this porous coordination polymer is substantially stiffer than normal polymers. This progress in characterizing mechanical properties of MOFs has been made possible by the use of high quality, oriented thin films grown using liquid phase epitaxy on modified Au substrates.

A technique to measure strain distributions in single wood pulp fibers

Treesearch

Laurence Mott; Stephen M. Shaler; Leslie H. Groom

1996-01-01

Environmental scanning electron microscopy (ESEM) and digital image correlation (DIC) were used to measure microstrain distributions on the surface of wood pulp fibers. A loading stage incorporating a fiber gripping system was designed and built by the authors. Fitted to the tensile substage of an ESEM or a Polymer Laboratories MINIMAT tester, it provided a reliable...

Cu(II) coordination polymers constructed by tetrafluoroterephthalic acid and varied imidazole-containing ligands: Syntheses, structures and properties

NASA Astrophysics Data System (ADS)

Liu, Kang; Sun, Yayong; Deng, Liming; Cao, Fan; Han, Jishu; Wang, Lei

2018-02-01

Six new copper(II) coordination polymers combining 2,3,5,6-tetrafluoroterephthalatic acid (H2tfBDC) and diverse imidazole-containing ligands, {[Cu(tfBDC)(1,2-bix)2]·2(H2O)}n (1), {Cu(tfBDC)(Im)2}n (2), {[Cu(1,4-bmimb)2(H2O)]·(tfBDC)·2(H2O)}n (3), {Cu(1,4-bimb)2(H2O)2·(tfBDC)}n (4), {[Cu(1,3-bix)2(H2O)2]·(tfBDC)·6(H2O)}n (5) and {[Cu(1,4-bix)2(H2O)2]·(tfBDC)·(1,4-bix)·4(H2O)}n (6) (1,2-bix = 1,2-bis(imidazole-1-ylmethyl)-benzene, Im = imidazole, 1,4-bmimb = 1,4-bis((2-methyl-1H-imidazol-1-yl)methyl)benzene, 1,4-bimb = 1,4-bis(imidazol-1-yl)-butane, 1,3-bix = 1,3-bis(imidazole-1-ylmethyl)-benzene, 1,4-bix = 1,4-bis(imidazole-1-ylmethyl)-benzene), have been obtained and structurally verified by single-crystal X-ray diffraction analyses and further characterized by powder X-ray diffraction (PXRD), elemental analyses and infrared spectroscopy (IR). Single crystal X-ray diffraction analysis revealed that 1 is 2D 4-connected sql topology (point symbol: {44·62}) based on a single metal ion node. Compound 2 is characterized as an infinite 1D chain structure, which is further extended into a 2D layer through N-H···O hydrogen bonds and then a 3D supramolecular architecture via π···π stacking interactions. Note that 2 was prepared through an in situ ligand reaction in which N,N'-carbonyldiimidazole (cdi) broke up into imidazole ligand. Compound 3 possesses a 3D 4-fold interpenetrated architecture with 4-connected dia topology (Schläfli symbol: {66}) in which tfBDC2- is stabilized in the channel by hydrogen bonds. Compounds 4-6 are all linear 1D coordination polymers. In 4, the free tfBDC2- ligand acts as a μ4-bridge to link four coordinated water molecules from the chain to construct a 2D structure via hydrogen bonds. While in 5 and 6, the uncoordinated tfBDC2- ligands and multimeric water clusters is responsible for the conversion of these 1D coordination polymers into 3D supramolecular assemblies through O-H⋯O hydrogen bonding interactions. Moreover, the UV-vis spectra and thermal stability of 1-6 are discussed in detail.

Design, construction, and testing a purpose-built climate-controlled solvent vapor annealing chamber for guided self-assembly of block polymer thin films

NASA Astrophysics Data System (ADS)

Gnabasik, Ryan; Haase, Rustin; Baruth, Andrew

2014-03-01

Despite its efficacy to produce well-ordered, periodic nanostructures, the intricate role multiple parameters play in solvent vapor annealing has not been fully established. In solvent vapor annealing a thin polymer film is exposed to the vapors of a solvent(s) thus forming a swollen and mobile layer to direct the self-assembly process at the nanoscale. Recent developments in both theory and experiment have directly identified critical parameters, but controlling them in any systematic way has proven non-trivial. These identified parameters include vapor pressure, solvent concentration in the film, and, critically, the solvent evaporation rate. To explore their role, a purpose-built solvent vapor annealing chamber was designed and constructed. The all-metal chamber is inert to solvent exposure and pneumatically actuated valves allow for precision timing in the introduction and withdrawal of solvent vapor. Furthermore, the mass flow controlled inlet, chamber pressure gauges, in situ spectral reflectance-based thickness monitoring, and high precision micrometer relief valve, give real-time monitoring and control during the annealing and evaporation phases. Using atomic force microscopy to image the annealed films, we are able to map out the parameter space for a series of polystyrene- b-polylactide (Mn = 75 kg/mol and fPLA = 0.28) block polymer thin films with an intrinsic cylindrical morphology and identify their role in directed assembly. Funded by Creighton University Summer Research Grant.

Engineering responsive polymer building blocks with host-guest molecular recognition for functional applications.

PubMed

Hu, Jinming; Liu, Shiyong

2014-07-15

CONSPECTUS: All living organisms and soft matter are intrinsically responsive and adaptive to external stimuli. Inspired by this fact, tremendous effort aiming to emulate subtle responsive features exhibited by nature has spurred the invention of a diverse range of responsive polymeric materials. Conventional stimuli-responsive polymers are constructed via covalent bonds and can undergo reversible or irreversible changes in chemical structures, physicochemical properties, or both in response to a variety of external stimuli. They have been imparted with a variety of emerging applications including drug and gene delivery, optical sensing and imaging, diagnostics and therapies, smart coatings and textiles, and tissue engineering. On the other hand, in comparison with molecular chemistry held by covalent bonds, supramolecular chemistry built on weak and reversible noncovalent interactions has emerged as a powerful and versatile strategy for materials fabrication due to its facile accessibility, extraordinary reversibility and adaptivity, and potent applications in diverse fields. Typically involving more than one type of noncovalent interactions (e.g., hydrogen bonding, metal coordination, hydrophobic association, electrostatic interactions, van der Waals forces, and π-π stacking), host-guest recognition refers to the formation of supramolecular inclusion complexes between two or more entities connected together in a highly controlled and cooperative manner. The inherently reversible and adaptive nature of host-guest molecular recognition chemistry, stemming from multiple noncovalent interactions, has opened up a new platform to construct novel types of stimuli-responsive materials. The introduction of host-guest chemistry not only enriches the realm of responsive materials but also confers them with promising new applications. Most intriguingly, the integration of responsive polymer building blocks with host-guest recognition motifs will endow the former with further broadened responsiveness to external stimuli and accordingly more sophisticated functions. In this Account, we summarize recent progress in the field of responsive polymeric materials containing host-guest recognition motifs with selected examples and highlight their versatile functional applications, whereas small molecule-oriented host-guest supramolecular systems are excluded. We demonstrate how the introduction of host-guest chemistry into conventional polymer systems can modulate their responsive modes to external stimuli. Moreover, the responsive specificity and selectivity of polymeric systems can also be inherited from the host-guest recognition motifs, and these features provide extra advantages in terms of function integration. The following discussions are categorized in terms of design and functions, namely, host-guest chemistry toward the fabrication of responsive polymers and assemblies, optical sensing and imaging, drug and gene delivery, and self-healing materials. A concluding remark on future developments is also presented. We wish this prosperous field would incur more original and evolutionary ideas and benefit fundamental research and our daily life in a more convenient way.

Synthesis of non-toxic As and Cr nanoparticles through redox activity of highly flexible layered coordination polymer of Ni(II).

PubMed

Agarwal, Rashmi A

2018-03-09

A simple method for the sequestration of As(III) and Cr(VI) from water has been demonstrated by utilizing a highly flexible porous coordination polymer (PCP) of Ni(II) in its as synthesized form or without solvent removal. This PCP reduces the high toxicity of As(III) and Cr(VI) ions into non-toxic As(0) and Cr/Cr 2 O 3 /CrO 2 (zero, tri and tetravalent) nanoparticles (NPs) within its pores, and this is characterized by powder x-ray diffraction, x-ray photoelectron spectroscopy and high-resolution transmission electron microscopy analysis. The high functionality of this polymer is due to the presence of monodentate carboxylate groups of a benzenetricarboxylate linker, which provide anchoring sites to the metal ions of the metal precursors. Due to the highly oxidising nature of these toxic ions, a redox reaction takes place between the framework metal ions and toxic metal ions, which is explained by an electron paramagnetic resonance study. This is the first report to synthesize non-toxic, as well as useful, NPs of As and Cr from their highly toxic ions within the cavities of a PCP for remediation of the toxic waste stream and contaminated waste water.

Flexible porous coordination polymer of Ni(II) for developing nanoparticles through acid formation and redox activity of the framework

NASA Astrophysics Data System (ADS)

Agarwal, Rashmi A.

2017-10-01

Immobilization of the nanoparticles (NPs) in a two dimensional porous coordination polymer (PCP) is currently an emerging field for a number of applications. But still it is a great challenge to fabricate any specified metal NPs in a single network. Herein the synthesis of Au, Pd, Mn, Fe, Cu, Zn, Mg, Li, Fe/Cu, Zn/Mg etc, NPs in a highly flexible PCP of Ni(II); {[Ni3(TBIB)2(BTC)2(H2O)6]·5C2H5OH·9H2O}n [TBIB = 1,3,5-tri(1H-benzo[d]imidazol-1-yl)benzene, H3BTC = 1,3,5-benzenetricarboxylic acid] have been reported. This universal host is able to grow mixed metal NPs from mixed metal precursors. Monodentate carboxylate groups of BTC linker act as anchoring sites for the metal ions of the metal precursors. This is the main driving force to grow NPs within the cavities along with the high flexibility of this polymer at room temperature. Mechanism involves acid formation followed by redox reaction to synthesize metal NPs explained by EPR and FTIR. Paramagnetic properties have been shown by as-synthesized Fe NPs integrated framework at room temperature under applied magnetic field up to 17,500 Oe.

Synthesis of non-toxic As and Cr nanoparticles through redox activity of highly flexible layered coordination polymer of Ni(II)

NASA Astrophysics Data System (ADS)

Agarwal, Rashmi A.

2018-03-01

A simple method for the sequestration of As(III) and Cr(VI) from water has been demonstrated by utilizing a highly flexible porous coordination polymer (PCP) of Ni(II) in its as synthesized form or without solvent removal. This PCP reduces the high toxicity of As(III) and Cr(VI) ions into non-toxic As(0) and Cr/Cr2O3/CrO2 (zero, tri and tetravalent) nanoparticles (NPs) within its pores, and this is characterized by powder x-ray diffraction, x-ray photoelectron spectroscopy and high-resolution transmission electron microscopy analysis. The high functionality of this polymer is due to the presence of monodentate carboxylate groups of a benzenetricarboxylate linker, which provide anchoring sites to the metal ions of the metal precursors. Due to the highly oxidising nature of these toxic ions, a redox reaction takes place between the framework metal ions and toxic metal ions, which is explained by an electron paramagnetic resonance study. This is the first report to synthesize non-toxic, as well as useful, NPs of As and Cr from their highly toxic ions within the cavities of a PCP for remediation of the toxic waste stream and contaminated waste water.

A 3D porous indium(III) coordination polymer involving in-situ ligand synthesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han Zhengbo, E-mail: ceshzb@lnu.edu.c; Song Yongjuan; Ji Jianwei

2009-11-15

The hydrothermal reaction of In{sup 3+} and 1,2,4-benzenetricarboxylic acid with the presence of piperazine leads to the generation of a novel 3D porous coordination polymer, [H{sub 3}O][In{sub 2}(btc)(bdc)(OH){sub 2}].5.5H{sub 2}O (1), (btc=1,2,4-benzenetricarboxylate, bdc=1,4-benzenedicarboxylate). Compound 1 crystallizes in orthorhombic space group Pbca with a=16.216(7) A, b=13.437(6) A, c=31.277(14) A, and Z=8. It is interesting to find that the in-situ decarboxylation reaction of 1,2,4-benzenetricarboxylate (btc) partially transformed into 1,4-benzenedicarboxylate (bdc) occurs. The 16 indium(III) centers were linked by four btc, four bdc and two mu{sub 2}-OH ligands to form a box-girder. The adjacent box-girders are further connected by the bdc and btcmore » ligands to generate a novel porous metal-organic framework containing nanotubular open channel with a cross-section of approximately 11.5x11.3 A{sup 2}. The micropores are occupied by lattice water molecules, and the solvent-accessible volume of the unit cell was estimated to be 3658.6 A{sup 3}, which is approximately 53.7% of the unit-cell volume (6815.4 A{sup 3}). - Graphical Abstract: The hydrothermal reaction of In{sup 3+} and 1,2,4-benzenetricarboxylic acid with the presence of piperazine leads to the generation of a novel 3D porous coordination polymer, [H{sub 3}O][In{sub 2}(btc)(bdc)(OH){sub 2}].5.5H{sub 2}O, (btc=1,2,4-benzenetricarboxylate, bdc=1,4-benzenedicarboxylate).« less

Coordination polymer-derived nano-sized zinc ferrite with excellent performance in nitro-explosive detection.

PubMed

Singha, Debal Kanti; Mahata, Partha

2017-08-29

Herein, a mixed metal coordination polymer, {(H 2 pip)[Zn 1/3 Fe 2/3 (pydc-2,5) 2 (H 2 O)]·2H 2 O} 1 {where H 2 pip = piperazinediium and pydc-2,5 = pyridine-2,5-dicarboxylate}, was successfully synthesized using a hydrothermal technique. To confirm the structure and phase purity of 1, single crystals of an isomorphous pure Fe compound, {(H 2 pip)[Fe(pydc-2,5) 2 (H 2 O)]·2H 2 O} 1a, were synthesized based on similar synthetic conditions. Single crystal X-ray data of 1a confirmed the one-dimensional anionic metal-organic coordination polymer hydrogen bonded with protonated piprazine (piperazinediium) and lattice water molecules. The phase purity of 1 and 1a were confirmed via powder X-ray diffraction. Compound 1 was systematically characterized using IR, TGA, SEM, and EDX elemental mapping analysis. Compound 1 was used as a single source precursor for the preparation of nano-sized ZnFe 2 O 4 via thermal decomposition. The as-obtained ZnFe 2 O 4 was fully characterized using PXRD, SEM, TEM, and EDX elemental mapping analysis. It was found that ZnFe 2 O 4 was formed in its pure form with particle size in the nano-dimension. The aqueous dispersion of nano-sized ZnFe 2 O 4 exhibits a strong emission at 402 nm upon excitation at 310 nm. This emissive property was employed for luminescence-based detection of nitroaromatic explosives in an aqueous medium through luminescence quenching for the first time. Importantly, selective detections have been observed for phenolic nitroaromatics based on differential luminescence quenching behaviour along with a detection limit of 57 ppb for 2,4,6-trinitrophenol (TNP) in water.

Manufacturing of embedded multimode waveguides by reactive lamination of cyclic olefin polymer and polymethylmethacrylate

NASA Astrophysics Data System (ADS)

Kelb, Christian; Rother, Raimund; Schuler, Anne-Katrin; Hinkelmann, Moritz; Rahlves, Maik; Prucker, Oswald; Müller, Claas; Rühe, Jürgen; Reithmeier, Eduard; Roth, Bernhard

2016-03-01

We demonstrate the manufacturing of embedded multimode optical waveguides through linking of polymethylmethacrylate (PMMA) foils and cyclic olefin polymer (COP) filaments based on a lamination process. Since the two polymeric materials cannot be fused together through interdiffusion of polymer chains, we utilize a reactive lamination agent based on PMMA copolymers containing photoreactive 2-acryloyloxyanthraquinone units, which allows the creation of monolithic PMMA-COP substrates through C-H insertion reactions across the interface between the two materials. We elucidate the lamination process and evaluate the chemical link between filament and foils by carrying out extraction tests with a custom-built tensile testing machine. We also show attenuation measurements of the manufactured waveguides for different manufacturing parameters. The lamination process is in particular suited for large-scale and low-cost fabrication of board-level devices with optical waveguides or other micro-optical structures, e.g., optofluidic devices.

Temperature dependence of conductivity measurement for conducting polymer

NASA Astrophysics Data System (ADS)

Gutierrez, Leandro; Duran, Jesus; Isah, Anne; Albers, Patrick; McDougall, Michael; Wang, Weining

2014-03-01

Conducting polymer-based solar cells are the newest generation solar cells. While research on this area has been progressing, the efficiency is still low because certain important parameters of the solar cell are still not well understood. It is of interest to study the temperature dependence of the solar cell parameters, such as conductivity of the polymer, open circuit voltage, and reverse saturation current to gain a better understanding on the solar cells. In this work, we report our temperature dependence of conductivity measurement using our in-house temperature-varying apparatus. In this project, we designed and built a temperature varying apparatus using a thermoelectric cooler module which gives enough temperature range as we need and costs much less than a cryostat. The set-up of the apparatus will be discussed. Temperature dependence of conductivity measurements for PEDOT:PSS films with different room-temperature conductivity will be compared and discussed. NJSGC-NASA Fellowship grant

Two isomorphous Co(ii) coordination polymers based on new α,α-disubstituted derivatives of zoledronic acid: synthesis, structures and properties.

PubMed

Rojek, Tomasz; Goldeman, Waldemar; Slepokura, Katarzyna; Duczmal, Marek; Wojciechowska, Agnieszka; Matczak-Jon, Ewa

2017-05-30

Two novel α,α-disubstituted derivatives of zoledronic acid, namely 1-hydroxy-2-(1H-imidazol-1-yl)-2-methylpropylidene-1,1-diphosphonic acid (H 4 L1) and 1-hydroxy-2-[1-(1H-imidazol-1-yl)cyclopropyl]ethylidene-1,1-diphosphonic acid (H 4 L2) were synthesized and structurally characterized by single-crystal X-ray diffraction. The reaction of cobalt acetate with H 4 L1 and H 4 L2 carried out under hydrothermal conditions afforded two isomorphous Co 3 (HL1) 2 (H 2 O) 6 ·6H 2 O (1a) and Co 3 (HL2) 2 (H 2 O) 6 ·6H 2 O (2a) complexes. Both compounds are characterized by means of X-ray crystallography, IR and NIR-Vis-UV spectroscopic methods. Furthermore, their magnetic properties and thermal stabilities are reported. The crystals of 1a and 2a feature infinite 1D polymeric chains built from alternately arranged dinuclear [Co2(HL1/HL2)(H 2 O) 2 ] 2 units and {Co1O 6 } octahedra running along the [1[combining macron]10] crystallographic direction. In both compounds, crystallographically distinct Co1 and Co2 atoms are six-coordinated. As is reflected in T values (T - index of tetragonality), the coordination environment of Co1 generates a slightly elongated octahedron (T = 0.94), whereas a slightly compressed octahedron (T = 1.06 for 1a and 1.05 for 2a) is formed around Co2. An assumption that the d-d type absorption is mainly attributed to the inversion related Co2 centers, whose population is two times higher than that of Co1, afforded a good correlation between calculated transition energies and experimental NIR-Vis-UV spectra. The magnetic susceptibility measurements analyzed in terms of a spin-3/2 Heisenberg trimer chain revealed that Co1Co2 interactions within the trimer are antiferromagnetic whereas Co2Co2 intertrimer interactions are ferromagnetic.

Synthesis and redox activity of "clicked" triazolylbiferrocenyl polymers, network encapsulation of gold and silver nanoparticles and anion sensing.

PubMed

Rapakousiou, Amalia; Deraedt, Christophe; Irigoyen, Joseba; Wang, Yanlan; Pinaud, Noël; Salmon, Lionel; Ruiz, Jaime; Moya, Sergio; Astruc, Didier

2015-03-02

The design of redox-robust polymers is called for in view of interactions with nanoparticles and surfaces toward applications in nanonetwork design, sensing, and catalysis. Redox-robust triazolylbiferrocenyl (trzBiFc) polymers have been synthesized with the organometallic group in the side chain by ring-opening metathesis polymerization using Grubbs-III catalyst or radical polymerization and with the organometallic group in the main chain by Cu(I) azide alkyne cycloaddition (CuAAC) catalyzed by [Cu(I)(hexabenzyltren)]Br. Oxidation of the trzBiFc polymers with ferricenium hexafluorophosphate yields the stable 35-electron class-II mixed-valent biferrocenium polymer. Oxidation of these polymers with Au(III) or Ag(I) gives nanosnake-shaped networks (observed by transmission electron microscopy and atomic force microscopy) of this mixed-valent Fe(II)Fe(III) polymer with encapsulated metal nanoparticles (NPs) when the organoiron group is located on the side chain. The factors that are suggested to be synergistically responsible for the NP stabilization and network formation are the polymer bulk, the trz coordination, the nearby cationic charge of trzBiFc, and the inter-BiFc distance. For instance, reduction of such an oxidized trzBiFc-AuNP polymer to the neutral trzBiFc-AuNP polymer with NaBH4 destroys the network, and the product flocculates. The polymers easily provide modified electrodes that sense, via the oxidized Fe(II)Fe(III) and Fe(III)Fe(III) polymer states, respectively, ATP(2-) via the outer ferrocenyl units of the polymer and Pd(II) via the inner Fc units; this recognition works well in dichloromethane, but also to a lesser extent in water with NaCl as the electrolyte.

Syntheses, structures and properties of three new two-dimensional Cu(I)-Ln(III) heterometallic coordination polymers based on 2,2'-dipyridyl-5,5'-dicarboxylate ligands.

PubMed

Zhao, Junwei; Cheng, Yamin; Shang, Sensen; Zhang, Fang; Chen, Li; Chen, Lijuan

2013-12-01

Three new two-dimensional Cu(I)-Ln(III) heterometallic coordination polymers [Ln(III)Cu2(I)(Hbpdc)4] · Cl · xH2O [Ln(III) = La(III), x = 8 (1); Ln(III) = Pr(III), x=9 (2); Ln(III) = Eu(III), x = 8 (3)] (H2bpdc = 2,2'-bipyridyl-5,5'-dicarboxylic acid) have been prepared under hydrothermal conditions and structurally characterized by elemental analyses, inductively coupled plasma atomic emission spectrometry (ICP-AES) analyses, IR spectra, X-ray photoelectron spectroscopy (XPS) and single-crystal X-ray diffraction. X-ray diffraction indicates that the isomorphic 1-3 display the two-dimensional sheet structure constructed from [Cu(I)(Hbpdc)2](-) fragments through Ln(3+) connectors. Moreover, the solid-state photoluminescence measurements of 3 indicate that the Eu(III) ions, Hbpdc(-) ligands and Cu(I) cations make contributions to its luminescent properties simultaneously. Copyright © 2013 Elsevier B.V. All rights reserved.

Synthesis, crystal structure and valence tautomerism of a 4,4‧-bipyridine-bridged one-dimensional chiral cobalt complex

NASA Astrophysics Data System (ADS)

Cheng, Wei-Qin; Li, Guo-Ling; Zhang, Ran; Ni, Zhong-Hai; Wang, Wen-Feng; Sato, Osamu

2015-05-01

A linear-chain cobalt coordination polymer, [Co(2,3-LH2)2(4,4‧-bipy)]ṡ2H2Oṡ4,4‧-bipy]n (1) (2,3-LH2 = 2,3-tetrahydroxy-9,10-dimethyl-9,10-dihydro- 9,10-ethanoanthracene, 4,4‧-bipy = 4,4‧-bipyridine), has been synthesized and structurally characterized. Single-crystal X-ray analysis reveals that complex 1 is a chiral polymer assemblied from achiral components. The complex 1 crystallizes in the chiral space group P3221 and the central Co ion has a slightly distorted octahedral coordination environment. The temperature dependence of magnetic susceptibility indicates that the complex 1 undergoes valence tautomeric interconversion between low-spin ls-[CoIII(2,3-LH2Cat)(2,3-LH2SQ)] and high-spin hs-[CoII(2,3-LH2SQ)2] (2,3-LH2Cat = 2,3-LH2catecholate, 2,3-LH2SQ = 2,3-LH2semiquinone).

N-donor co-ligands driven two new Co(II)- coordination polymers with bi- and trinuclear units: Crystal structures, and magnetic properties

NASA Astrophysics Data System (ADS)

Zhou, Zhi-Hang; Han, Min-Le; Wu, Ya-Pan; Dong, Wen-Wen; Li, Dong-Sheng; Lu, Jack Y.

2016-10-01

Two new Co(II) coordination polymers(CPs), namely [Co2(bpe)2(Hbppc)]n (1) and [Co3(μ3-OH)(bppc)(bpm)(H2O)]·3H2O (2) (H5bppc=biphenyl-2,4,6,3‧,5‧-pentacarboxylic acid, bpe=1,2-bis(4-pyridyl)ethene, bpm=bis(4-pyridyl)amine), have been obtained and characterized by elemental analysis, single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), IR spectra and thermogravimetric analysis (TGA). 1 shows a binodal (4,6)-connected fsc net with a (44·610·8)(44·62) topology, while 2 shows a binodal (5,7)-connected 3D network based on trinuclear [Co3(μ3-OH)]5+ units with unusual (3.46.52.6)(32.46.57.65.7) topology. Variable-temperature magnetic susceptibility measurements reveals that complex 1 shows ferromagnetic interactions between the adjacent Co(II) ions, whereas 2 is a antiferromagnetic system.

Metal-metal interactions in tetrakis(diphenylphosphino)benzene-bridged dimetallic complexes and their related coordination polymers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Pei-Wei; Fox, M.A.

1994-06-22

Electrochemical, EPR, and spectroelectrochemical methods have been used to probe electronic coupling through a 1,2,4,5-tetrakis(diphenylphosphino)benzene bridging ligand connecting metal centers in several Ni-, Pd-, and Pt-containing dimetallic complexes. These dimetalated complexes showed weak intervalence charge transfer (IT) bands and slightly shifted redox potentials in comparison with their monometallic models. A Marcus-Hush analysis of the energies of the IT bands for the electrochemically generated mixed-valence heterodimetallic complexes (Ni{sup o}-Pd{sup II} and Ni{sup o}-Pt{sup II}, respectively) established the magnitude of intermetallic electronic coupling. The weak thermal coupling observed in these dimetalated complexes is consistent with the very low conductivities (10{sup {minus}8}-10{sup {minus}10}{omega}{supmore » -1} cm{sup {minus}1}) observed in the polymeric analogs of these complexes, namely, the newly prepared metal coordination polymers (M = Ni{sup II}, Pd{sup II}, Pt{sup II}) with 1,2,4,5-tetrakis(diphenylphosphino)benzene.« less

Design and synthesis of two luminescent Zn(II)-based coordination polymers with different structures regulated by different solvent system

NASA Astrophysics Data System (ADS)

Wu, Wei-Ping; Wen, Gui-Lin; Liao, Yi; Wang, Jun; Lu, Lu; Wu, Yu; Xie, Bin

2016-08-01

Two new coordination polymers (CPs) [Zn(HL)(H2O)]n (1) and [Zn3(L)2(H2O)2]n·(H2O)n (2), based on a multifunctional ligand combined carboxylate groups and a nitrogen donor group 5-(6-carboxypyridin-2-yl)isophthalic acid (H3L), have been synthesized under different solvent media and fully characterized by powder X-ray diffraction (PXRD), infrared (IR) spectra, elemental analyses (EA) and thermogravimetric analyses (TGA). Single-crystal X-ray diffraction analysis reveals that 1 shows 1D dimeric chain structure, while 2 gives a 3D dense packing framework. Topology analysis illustrates that 2 can be simplified as a 3-nodal net (4, 5, 6-connected net) with the point symbol of {44·62}{46·64}2{48·66·8}. In addition, solid state luminescent properties of two complexes have also been studied in detail, which may act as the potential optical materials.

Two intriguing hydroxy-copper(II) coordination polymers with bis(triazole) and bicarboxylate ligands: Syntheses, structures and photocatalytic degradation of organic dyes

NASA Astrophysics Data System (ADS)

Zhao, Shan; Zheng, Tian-Rui; Shi, Lu-Lu; Li, Ke; Li, Bao-Long; Li, Hai-Yan

2017-09-01

Two intriguing coordination polymers [Cu2(OH)(mbtx)(sip)(H2O)2]n (1) and {[Cu3(OH)2(mbtx)(nip)2]·H2O}n (2) were synthesized by the hydrothermal method and characterized by elementary analysis, IR, PXRD, diffuse reflectance spectra and single-crystal X-ray diffraction (mbtx = 1,3-bis(1,2,4-triazol-4-yl)benzene, sip = sulfoisophthalate, nip = 5-nitroisophthalate). 1 shows an unusual 3-connected 2D network based on the dimeric hydroxy-copper(II) cluster [Cu2(μ-OH)] with the point symbol of 63. 2 exhibits an unusual 3D network based on 1D hydroxyl-copper(II) chains [Cu3(OH)2]n. 1 and 2 are highly efficient and universal photocatalysts for the degradation of the organic dyes such as methyl orange (MO), methylene blue (MB) and rhodamine B (RhB) under UV irradiation. The photocatalytic mechanism was supposed.

An efficient p-n heterojunction photocatalyst constructed from a coordination polymer nanoplate and a partically reduced graphene oxide for visible-light hydrogen production.

PubMed

Xu, Xinxin; Lu, Tingting; Liu, Xiaoxia; Wang, Xiuli

2015-10-05

A new p-n heterojunction photocatalyst has been synthesized successfully through chemical-bond-mediated combination of coordination polymer nanoplates (CPNPs) and partially reduced graphene oxide (PRGO) with a simple colloidal blending process. Photocatalytic H2 production by the p-n heterojunction photocatalyst PRGO/CPNP was investigated under visible-light irradiation, which illustrates that PRGO/CPNP exhibits a much higher photocatalytic H2 production rate than neat the CPNPs. The improvement of this photocatalytic property can be attributed to the inner electrical field formed in the p-n heterojunction, which impedes recombination of photogenerated electrons and holes. In PRGO/CPNP, the existence of the p-n heterojunction has been confirmed by electrochemical methods clearly. For PRGO/CPNP, the reductive degree of the PRGO has a great influence on the H2 production rate and an ideal condition to get a PRGO/CPNP photocatalyst with higher performance has been obtained. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

pH-Dependent two novel heteronuclear Cu(II)/Sr(II) coordination polymers constructed from 1,3,5-benzenetricarboxylic acid: Synthesis, crystal structures and properties

NASA Astrophysics Data System (ADS)

Sun, Qiao-Zhen; Yin, Yi-Biao; Pan, Jun-Qiao; Chai, Li-Yuan; Su, Nan; Liu, Hui; Zhao, Yi-Lin; Liu, Xing-Tao

2016-02-01

Two novel heteronuclear coordination polymers, namely, [CuSr2(BTC)2]·10H2O (1) and [Cu2Sr(H4TMA)2]·4H2O (2) (H3BTC = 1,3,5-benzenetricarboxylic acid, H4TMA = 2-hydroxytrimesic acid) were hydrothermally synthesized as pH-dependent products and characterized by elemental analysis (EA), infrared spectroscopy (IR) and single crystal X-ray diffraction. For compound 1, it displays a 3D structure with (2,5,6)-connected net topology. For 2, the H3BTC ligand is oxidized into H4TMA and compound 2 features a 2D layer structure, which is further linked by Cu⋯Cu and Cu⋯O supramolecular interactions into a 3D structure. The results show that the pH plays a crucial role in determining the structure of the compounds. In addition, thermalgravimetric analysis of compounds 1-2 and luminescence property of 1 are also investigated.

Three coordination polymers based on a star-like geometry 4, 4', 4'' -nitrilotribenzoic acid ligand and their framework dependent luminescent properties

NASA Astrophysics Data System (ADS)

Hu, Zhiyong; Zhao, Meng; Su, Jian; Xu, Shasha; Hu, Lei; Liu, Hui; Zhang, Qiong; Zhang, Jun; Wu, Jieying; Tian, Yupeng

2018-02-01

Three novel coordination polymers, [Zn(μ2-HTCA)(Phen)]n (1), {[Cd(μ3-HTCA)(Phen)]·2H2O}n (2), [Mn(μ2-HTCA)(Phen)(H2O)]n (3) were prepared by hydrothermal synthesis from the 4, 4', 4''-nitrilotribenzoicacid (H3TCA) and 1, 10-phenanthroline monohydrate (Phen) with different transition metal salts, which were characterized by elemental analysis, IR spectra, powder and single-crystal X-ray diffraction and thermogravimetric analysis. The photophysical properties of the complexes were investigated by solid-state diffuse reflectance spectra, photoluminescent properties, lifetime and quantum yield. For these complexes, it was found that the band gaps follow the order: 3 ＜ 2 ＜ 1 ＜ 2.80 eV, fluorescence intensity order: 1 ＞ H3TCA ＞ 2 ＞ 3; quantum yield order: H3TCA ＞ 1 ＞ 2 ＞ 3; while the lifetime order: 1 ＞ 2 ＞ H3TCA ＞ 3.

A Eu/Tb mixed lanthanide coordination polymer with rare 2D thick layers: Synthesis, characterization and ratiometric temperature sensing

NASA Astrophysics Data System (ADS)

Zhu, Yuanyuan; Xia, Tifeng; Zhang, Qi; Cui, Yuanjing; Yang, Yu; Qian, Guodong

2018-03-01

A series of lanthanide coordination polymers LnBTPTA (Ln = Eu, Tb, EuxTb1-x), was synthesized using a tricarbocylic ligand 4,4‧,4‧‧-(benzene-1,3,5-triyltris(1H-pyrazole-3,1-diyl))tribenzoic acid (H3BTPTA). X-ray single crystal analyses reveal that the asymmetric unit cell contains seven crystallographically independent metal ions and seven crystallographically independent ligands which is quite unusual. The 3D framework is comprised of 2D thick layers stacked through van der Waals force, π-π interactions and hydrogen bonding interactions. Eu0.0316Tb0.9684BTPTA presents a dual-emission of Tb3+ at 543 nm and Eu3+ at 617 nm, and the intensity ratio shows an excellent linear relationship with the temperature changing in 25-225 K. The relative sensitivity 0.45-5.12% K-1 is much higher than those have been reported in the same detection range.

Perturbing Tandem Energy Transfer in Luminescent Heterobinuclear Lanthanide Coordination Polymer Nanoparticles Enables Real-Time Monitoring of Release of the Anthrax Biomarker from Bacterial Spores.

PubMed

Gao, Nan; Zhang, Yunfang; Huang, Pengcheng; Xiang, Zhehao; Wu, Fang-Ying; Mao, Lanqun

2018-06-05

Lanthanide-based luminescent sensors have been widely used for the detection of the anthrax biomarker dipicolinic acid (DPA). However, mainly based on DPA sensitization to the lanthanide core, most of them failed to realize robust detection of DPA in bacterial spores. We proposed a new strategy for reliable detection of DPA by perturbing a tandem energy transfer in heterobinuclear lanthanide coordination polymer nanoparticles simply constructed by two kinds of lanthanide ions, Tb 3+ and Eu 3+ , and guanosine 5'-monophosphate. This smart luminescent probe was demonstrated to exhibit highly sensitive and selective visual luminescence color change upon exposure to DPA, enabling accurate detection of DPA in complex biosystems such as bacterial spores. DPA release from bacterial spores on physiological germination was also successfully monitored in real time by confocal imaging. This probe is thus expected to be a powerful tool for efficient detection of bacterial spores in responding to anthrax threats.

Solvothermal synthesis and structure of coordination polymers of Nd(III) and Dy(III) with rigid isophthalic acid derivatives and flexible adipic acid

NASA Astrophysics Data System (ADS)

Kariem, Mukaddus; Kumar, Manesh; Yawer, Mohd; Sheikh, Haq Nawaz

2017-12-01

Two new coordination polymers (CPs) with the formula [Nd(hip)(adip) 0.5(H2O)2]n.nH2O (1) and [Dy(aip)(adip)0.5(H2O)2]n.nH2O (2) were synthesized by self-assembly of lanthanide salts with rigid [5-hydroxyisophthalic acid (H2hip)], [5-aminoisophthalic acid (H2aip)] and flexible [adipic acid (H2adip)] linkers under solvothermal conditions. The CPs 1 &2 crystallize in monoclinic C2/c space group. Both the CPs have 1D linear ladder shaped extension with the linkages having the backbone of hip2-, aip2- and adip2- ligands. The 1D linear ladder chains generate three dimensional (3D) supramolecular frameworks via significant π-π and hydrogen bonding interactions. The CP 2 (Dy) emit strong ligand sensitized characteristic f-f luminescence emission. The CP 2 also exhibit weak ferromagnetic interactions at low temperatures.

Chiral expression from molecular to macroscopic level via pH modulation in terbium coordination polymers.

PubMed

Huang, Jian; Ding, Hong-Ming; Xu, Yan; Zeng, Dai; Zhu, Hui; Zang, Dong-Mian; Bao, Song-Song; Ma, Yu-Qiang; Zheng, Li-Min

2017-12-14

Chiral expression from the molecular to macroscopic level is common in biological systems, but is difficult to realise for coordination polymers (CPs). The assembly of homochiral CPs in both crystalline and helical forms can provide a bridge for understanding the relationship between the molecular and macroscopic scales of chirality. Herein, we report homochiral helices of [Tb(R- or S-pempH) 3 ]∙2H 2 O (R - or S -1) (pempH 2  = (1-phenylethylamino)methylphosphonic acid) and their crystalline counterparts (R - or S -3), which are formed at different pH of the reaction mixtures under hydrothermal conditions. By combining the experiments and molecular simulations, we propose that the formation of helices of R -1 or S -1 occurs via a hierarchical self-assembly route, which involves twisted packing due to the geometric incompatibility of the different types of chains. The observed chiral transcription from molecules to morphologies is significant for understanding bio-related self-assembly processes on the nano- to macro-scale.

Syntheses, structures and properties of metal-carboxylate chain-based coordination polymers (CPs) with 1,1‧:4‧,1″-terphenyl-2‧,4,4″,5‧-tetracarboxylate

NASA Astrophysics Data System (ADS)

Zhou, Xinhui; Song, Lin; Li, Liang; Yang, Tao

2016-09-01

Two coordination polymers (CPs) {[Mg2L(μ2-H2O) (μ2-DMA)]·DMA}n (1), and [Ag4L(DMF)2]n (2) (H4L = 1,1‧:4‧,1″-terphenyl-2‧,4,4″,5‧-tetracarboxylic acid, DMA = N,N-dimethylacetamine, DMF = N,N-dimethylformamide) have been synthesized and structurally characterized. In 1 and 2, there exist a series of parallel aligned Msbnd Osbnd C chains, which are linked along two directions by para-terphenyl moieties of L4- ligands to lead to the metal-carboxylate chain-based three-dimensional frameworks. The photoluminescence properties of the compounds 1 and 2 have also been investigated. 1 displays blue-violet light emission with the emission maximum at 380 nm. 2 exhibits a broad emission peak from 300 to 800 nm with an emission maximum at 484 nm and some of the shoulder peaks.

Two novel metal-organic coordination polymers based on diphosphonate and oxalate: Synthesis, structures and properties

NASA Astrophysics Data System (ADS)

Niu, Qing-Jun; Zheng, Yue-Qing; Zhou, Lin-Xia; Zhu, Hong-Lin

2015-07-01

Two 2-(1-imidazole)-1-hydroxyl-1,1'-ethylidenediphosphonato and oxalic acid bridged coordination polymers (H2en)[Co3(H2zdn)2(ox)(H2O)2] (1) and Cd2(H2zdn)(ox)0.5(H2O) (2) (2-(1-imidazole)-1-hydroxyl-1,1'-ethylidenediphosphonic acid=H5zdn; oxalic acid=H2ox) were synthesized under hydrothermal conditions and characterized by the infrared (IR), thermogravimetric analyses (TGA), elemental analyses (EA) and X-ray diffraction (XRD). Compound 1 is bridged by phosphonate anions to 1D chain, and further linked by oxalate anions to 2D layer. Compound 2 is bridged by O-P-O units of H5zdn to the layer, and then pillared by oxalate anions to generate 3D frameworks. Compound 1 shows anti-ferromagnetic behaviors analyzed with the temperature-dependent zero-field ac magnetic susceptibilities, while compound 2 exhibits an influence on the luminescent property.

Efficient tetracycline adsorption and photocatalytic degradation of rhodamine B by uranyl coordination polymer

NASA Astrophysics Data System (ADS)

Ren, Ya-Nan; Xu, Wei; Zhou, Lin-Xia; Zheng, Yue-Qing

2017-07-01

Two mixed uranyl-cadmium malonate coordination polymers [(UO2)2Cd(H-bipy)2(mal)4(H2O)2]·4H2O 1 and [(UO2)Cd(bipy)(mal)2]·H2O 2 (H2mal = malonic acid, bipy =4,4‧-bipyridine) have been synthesized in room temperature. Compound 1 represents a one-dimensional (1D) chain assembly of Cd(II) ions, uranyl centers and malonate ligands. Compound 2 exhibits a two-dimensional (2D) 2D +2D → 3D polycatenated framework based on inclined interlocked 2D 44 sql grids. The two compounds have been characterized by elemental analysis, IR and UV-vis spectroscopy, thermal analysis, powder X-ray diffraction and photoluminescence spectroscopy. And the ferroelectric property of 2 also has been studied. Moreover, compound 2 exhibits good photocatalytic activity for dye degradation under UV light and is excellent adsorbent for removing tetracycline antibiotics in the aqueous solution.

Renal-Clearable Ultrasmall Coordination Polymer Nanodots for Chelator-Free 64Cu-Labeling and Imaging-Guided Enhanced Radiotherapy of Cancer.

PubMed

Shen, Sida; Jiang, Dawei; Cheng, Liang; Chao, Yu; Nie, Kaiqi; Dong, Ziliang; Kutyreff, Christopher J; Engle, Jonathan W; Huang, Peng; Cai, Weibo; Liu, Zhuang

2017-09-26

Developing tumor-homing nanoparticles with integrated diagnostic and therapeutic functions, and meanwhile could be rapidly excreted from the body, would be of great interest to realize imaging-guided precision treatment of cancer. In this study, an ultrasmall coordination polymer nanodot (CPN) based on the coordination between tungsten ions (W VI ) and gallic acid (W-GA) was developed via a simple method. After polyethylene glycol (PEG) modification, PEGylated W-GA (W-GA-PEG) CPNs with an ultrasmall hydrodynamic diameter of 5 nm were rather stable in various physiological solutions. Without the need of chelator molecules, W-GA-PEG CPNs could be efficiently labeled with radioisotope 64 Cu 2+ , enabling positron emission tomography (PET) imaging, which reveals efficient tumor accumulation and rapid renal clearance of W-GA-PEG CPNs upon intravenous injection. Utilizing the radio-sensitizing function of tungsten with strong X-ray absorption, such W-GA-PEG CPNs were able to greatly enhance the efficacy of cancer radiotherapy in inhibiting the tumor growth. With fast clearance and little long-term body retention, those W-GA-PEG CPNs exhibited no appreciable in vivo toxicity. This study presents a type of CPNs with excellent imaging and therapeutic abilities as well as rapid renal clearance behavior, promising for further clinic translation.

Synthesis, Structure, White-Light Emission, and Temperature Recognition Properties of Eu/Tb Mixed Coordination Polymers.

PubMed

An, Ran; Zhao, Hui; Hu, Huai-Ming; Wang, Xiaofang; Yang, Meng-Lin; Xue, Ganglin

2016-01-19

Two series of Eu(III)/Tb(III) coordination polymers, [LnL(glu)]n·2nH2O (Ln = Eu (1), Tb (2)) and [LnL(glu)(H2O)]n (Ln = Eu (3), Tb (4)) [HL = (2-(2-sulfophenyl)imidazo(4,5-f)(1,10)-phenanthroline, H2glu = glutaric acid] have been hydrothermally synthesized by controlling the pH values and characterized by elemental analysis, infrared spectra, and single-crystal X-ray diffraction. Isomorphic compounds 1 and 2 exhibit 6-connected 3D network with the pcu topological net, containing left- and right-handed helical chains. Isomorphic compounds 3 and 4 show 3,4-connected 2D new topology with the point symbol of (4(2)·6(3)·8)(4(2)·6). Multicolor luminescence can be tailored from red to green regions by singly varying the mixing molar ratio of Eu(III)/Tb(III) cations. The mixing component of 1Eu/2Tb = 4:6 not only achieves white-light emission with the CIE coordinate of (0.323, 0.339) upon excitation at 405 nm but also presents a temperature recognition property with the significantly high sensitivity of 0.68% per K in the 50-225 K temperature range upon excitation at 370 nm.

High Anodic Performance of Co 1,3,5-Benzenetricarboxylate Coordination Polymers for Li-Ion Battery.

PubMed

Li, Chao; Lou, Xiaobing; Shen, Ming; Hu, Xiaoshi; Guo, Zhi; Wang, Yong; Hu, Bingwen; Chen, Qun

2016-06-22

We report the designed synthesis of Co 1,3,5-benzenetricarboxylate coordination polymers (CPs) via a straightforward hydrothermal method, in which three kinds of reaction solvents are selected to form CPs with various morphologies and dimensions. When tested as anode materials in Li-ion battery, the cycling stabilities of the three CoBTC CPs at a current density of 100 mA g(-1) have not evident difference; however, the reversible capacities are widely divergent when the current density is increased to 2 A g(-1). The optimized product CoBTC-EtOH maintains a reversible capacity of 473 mAh g(-1) at a rate of 2 A g(-1) after 500 galvanostatic charging/discharging cycles while retaining a nearly 100% Coulombic efficiency. The hollow microspherical morphology, accessible specific area, and the absence of coordination solvent of CoBTC-EtOH might be responsible for such difference. Furthermore, the ex situ soft X-ray absorption spectroscopy studies of CoBTC-EtOH under different states-of-charge suggest that the Co ions remain in the Co(2+) state during the charging/discharging process. Therefore, Li ions are inserted to the organic moiety (including the carboxylate groups and the benzene ring) of CoBTC without the direct engagement of Co ions during electrochemical cycling.

Variations of structures and solid-state conductivity of isomeric silver(I) coordination polymers having linear and V-shaped thiophene-centered ditriazole ligands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Bin; School of Environmental and Chemical Engineering, Nanchang Hangkong University, Nanchang, 330063; Geng, Jiao

2014-07-01

A pair of new linear and V-shaped acceptor–donor–acceptor (A−D−A) thiophene-centered ditriazole structural isomers, i.e., 2,5-di(1H-1,2,4-triazol-1-yl)thiophene (L{sup 1}) and 3,4-di(1H-1,2,4-triazol-1-yl)thiophene (L{sup 2}), has been synthesized and characterized. They are used as μ{sub 2}-bridging ligands to prepare a pair of silver(I) coordination polymers formulated as [Ag(L{sup 1})(NO{sub 3})]{sub n} (1) and [Ag(L{sup 2})(NO{sub 3})]{sub n} (2), which are also structural isomers at the supramolecular level. X-ray single-crystal diffraction analyses for 1 and 2 reveal that they exhibit the same one-dimensional (1D) coordination polymers but different structural architectures because of the distinguishable shape and configuration of isomeric ligands (L{sup 1} and L{sup 2})more » and the alterations of the coordination numbers. More interestingly, compared with the free ligands, 1D silver(I) polymeric isomers 1 and 2 show significant enhancement of solid-state conductivity to different extents (1.42×10{sup 4} and 2.17×10{sup 3} times), where 6.96 times' enhancement of solid-state conductivity from 1 to 2 has been observed. The formation of Ag–N coordinative bonds and the configurational discrepancy of L{sup 1} and L{sup 2} are believed to play important roles in facilitating the electron transport between molecules, which can also be supported by Density Function Theory calculations of their band gaps. - Graphical abstract: A pair of linear and V-shaped isomeric thiophene-centered ditriazole ligands (L{sup 1}) and L{sup 2} are used to prepare a pair of silver(I) polymeric isomers (1 and 2), where significant enhancement of solid-state conductivity to different extents are observed originating from the distinguishable shape and configuration of isomeric ligands. - Highlights: • A pair of linear and V-shaped thiophene-centered ditriazole structural isomers is prepared. • They are used as µ{sub 2}-bridging ligands to prepare a pair of silver(I) polymeric isomers. • Significant enhancement of solid-state conductivity is observed for each polymeric isomer.« less

Facile construction of terpridine-based metallo-polymers in hydrogels, crystals and solutions directed by metal ions.

PubMed

Li, Yajuan; Guo, Jiangbo; Dai, Bo; Geng, Lijun; Shen, Fengjuan; Zhang, Yajun; Yu, Xudong

2018-07-01

Driven by tunable metal-ligand interactions, a polydentate ligand TC containing terpyridine and carboxylic acid units was developed to construct metallo-polymers that showed multiple aggregation modes with controlled macroscopic properties. In the presence of different kind of Zn 2+ ions or NaOH, TC could form metallo-polymers via π-π stacking and metal-ligand interaction that further trapped water molecules, resulting in hydrogels and crystals. Moreover, these TC/Zn 2+ hydrogels could transform to soluble and fluorescent aggregates in the presence of NaOH due to the formation of binuclear metallo-polymers with enhanced ICT emission. The metal-ligand interactions tuned by different metal salts in gels, crystals, and sols were also studied and illustrated in detail, it was also proved that water was an essential linker for constructing Na + -based metallo-polymers from the TC/NaOH crystal data. This work demonstrated the engineered coordination pathways in generating controllable hydrogels and metallo-polymers for the first time, which led to novel approach for facilely constructing a number of hydrogels with tailorable macroscopic properties. Copyright © 2018 Elsevier Inc. All rights reserved.

Effect of degree of crosslinking and polymerization of 3D printable polymer/ionic liquid composites on performance of stretchable piezoresistive sensors

NASA Astrophysics Data System (ADS)

Lee, Jeongwoo; Faruk Emon, Md Omar; Vatani, Morteza; Choi, Jae-Won

2017-03-01

Ionic liquid (IL)/polymer composites (1-ethyl-3-methyl-imidazolium tetrafluoroborate (EMIMBF4)/2-[[(butylamino)carbonyl]oxy]ethyl acrylate (BACOEA)) were fabricated to use as sensing materials for stretchable piezoresistive tactile sensors. The detectability of the IL/polymer composites was enhanced because the ionic transport properties of EMIMBF4 in the composites were improved by the synergic actions between the coordinate sites generated by the local motion of BACOEA chain segments under enough activation energy. The performance of the piezoresistive sensors was investigated with the degree of crosslinking and polymerization of the IL/polymer composites. As the compressive strain was increased, the distance between two electrodes decreased, and the motion of polymer chains and IL occurred, resulting in a decrease in the electrical resistance of the sensors. We have confirmed that the sensitivity of the sensors are affected by the degree of crosslink and polymerization of the IL/polymer composites. In addition, all of the materials (skins, sensing material, and electrode) used in this study are photo-curable, and thus the stretchable piezoresistive tactile sensors can be successfully fabricated by 3D printing.

Characterization of MreB polymers in E. coli and their correlations to cell shape

NASA Astrophysics Data System (ADS)

Nguyen, Jeffrey; Ouzonov, Nikolay; Gitai, Zemer; Shaevitz, Joshua

2015-03-01

Shape influences all facets of how bacteria interact with their environment. The size of E. coli is determined by the peptidoglycan cell wall and internal turgor pressure. The cell wall is patterned by MreB, an actin homolog that forms short polymers on the cytoplasmic membrane. MreB coordinates the breaking of old material and the insertion of new material for growth, but it is currently unknown what mechanism sets the absolute diameter of the cell. Using new techniques in fluorescence microscopy and image processing, we are able to quantify cell shape in 3- dimensions and access previously unattainable data on the conformation of MreB polymers. To study how MreB affects the diameter of bacteria, we analyzed the shapes and polymers of cells that have had MreB perturbed by one of two methods. We first treated cells with the MreB polymerization-inhibiting drug A22. Secondly, we created point mutants in MreB that change MreB polymer conformation and the cell shape. By analyzing the correlations between different shape and polymer metrics, we find that under both treatments, the average helical pitch angle of the polymers correlates strongly with the cell diameter. This observation links the micron scale shape of the cell to the nanometer scale MreB cytoskeleton.

Commensurate Superstructure of the {Cu(NO3)(H2O)}(HTae)(Bpy) Coordination Polymer: An Example of 2D Hydrogen-Bonding Networks as Magnetic Exchange Pathway.

PubMed

Fernández de Luis, Roberto; Larrea, Edurne S; Orive, Joseba; Lezama, Luis; Arriortua, María I

2016-11-21

The average and commensurate superstructures of the one-dimensional coordination polymer {Cu(NO 3 )(H 2 O)}(HTae)(Bpy) (H 2 Tae = 1,1,2,2-tetraacetylethane, Bpy = 4,4'-bipyridine) were determined by single-crystal X-ray diffraction, and the possible symmetry relations between the space group of the average structure and the superstructure were checked. The crystal structure consists in parallel and oblique {Cu(HTae)(Bpy)} zigzag metal-organic chains stacked along the [100] crystallographic direction. The origin of the fivefold c axis in the commensurate superstructure is ascribed to a commensurate modulation of the coordination environment of the copper atoms. The commensurately ordered nitrate groups and coordinated water molecules establish a two-dimensional hydrogen-bonding network. Moreover, the crystal structure shows a commensurate to incommensurate transition at room temperature. The release of the coordination water molecules destabilizes the crystal framework, and the compound shows an irreversible structure transformation above 100 °C. Despite the loss of crystallinity, the spectroscopic studies indicate that the main building blocks of the crystal framework are retained after the transformation. The hydrogen-bonding network not only plays a crucial role stabilizing the crystal structure but also is an important pathway for magnetic exchange transmission. In fact, the magnetic susceptibility curves indicate that after the loss of coordinated water molecules, and hence the collapse of the hydrogen-bonding network, the weak anti-ferromagnetic coupling observed in the initial compound is broken. The electron paramagnetic resonance spectra are the consequence of the average signals from Cu(II) with different orientations, indicating that the magnetic coupling is effective between them. In fact, X- and Q-band data are reflecting different situations; the X-band spectra show the characteristics of an exchange g-tensor, while the Q-band signals are coming from both the exchange and the molecular g-tensors.

In Situ High Pressure Hydrogen Tribological Testing of Common Polymer Materials Used in the Hydrogen Delivery Infrastructure.

PubMed

Duranty, Edward R; Roosendaal, Timothy J; Pitman, Stan G; Tucker, Joseph C; Owsley, Stanley L; Suter, Jonathan D; Alvine, Kyle James

2018-03-31

High pressure hydrogen gas is known to adversely affect metallic components of compressors, valves, hoses, and actuators. However, relatively little is known about the effects of high pressure hydrogen on the polymer sealing and barrier materials also found within these components. More study is required in order to determine the compatibility of common polymer materials found in the components of the hydrogen fuel delivery infrastructure with high pressure hydrogen. As a result, it is important to consider the changes in physical properties such as friction and wear in situ while the polymer is exposed to high pressure hydrogen. In this protocol, we present a method for testing the friction and wear properties of ethylene propylene diene monomer (EPDM) elastomer samples in a 28 MPa high pressure hydrogen environment using a custom-built in situ pin-on-flat linear reciprocating tribometer. Representative results from this testing are presented which indicate that the coefficient of friction between the EPDM sample coupon and steel counter surface is increased in high pressure hydrogen as compared to the coefficient of friction similarly measured in ambient air.

Development and Verification of a Novel Robot-Integrated Fringe Projection 3D Scanning System for Large-Scale Metrology.

PubMed

Du, Hui; Chen, Xiaobo; Xi, Juntong; Yu, Chengyi; Zhao, Bao

2017-12-12

Large-scale surfaces are prevalent in advanced manufacturing industries, and 3D profilometry of these surfaces plays a pivotal role for quality control. This paper proposes a novel and flexible large-scale 3D scanning system assembled by combining a robot, a binocular structured light scanner and a laser tracker. The measurement principle and system construction of the integrated system are introduced. A mathematical model is established for the global data fusion. Subsequently, a robust method is introduced for the establishment of the end coordinate system. As for hand-eye calibration, the calibration ball is observed by the scanner and the laser tracker simultaneously. With this data, the hand-eye relationship is solved, and then an algorithm is built to get the transformation matrix between the end coordinate system and the world coordinate system. A validation experiment is designed to verify the proposed algorithms. Firstly, a hand-eye calibration experiment is implemented and the computation of the transformation matrix is done. Then a car body rear is measured 22 times in order to verify the global data fusion algorithm. The 3D shape of the rear is reconstructed successfully. To evaluate the precision of the proposed method, a metric tool is built and the results are presented.

A second polymorph of catena-poly[[(1,10-phenanthroline-κ2 N,N′)copper(II)]-di-μ-thio­cyanato-κ2 N:S;κ2 S:N

PubMed Central

Zhang, Shi-Shen; Chen, Li-Jiang; Han, Yi-Feng

2011-01-01

In the title coordination polymer, [Cu(NCS)2(C12H8N2)]n, the CuII atom is situated on a twofold rotation axis and is coordinated by two N atoms from the bidentate 1,10-phenanthroline ligand and four thio­cyanate groups to confer a CuN4S2 octa­hedral geometry and resulting in a layer structure extending parallel to (100). PMID:21753934

Quantifying care coordination using natural language processing and domain-specific ontology

PubMed Central

Popejoy, Lori L; Khalilia, Mohammed A; Popescu, Mihail; Galambos, Colleen; Lyons, Vanessa; Rantz, Marilyn; Hicks, Lanis; Stetzer, Frank

2015-01-01

Objective This research identifies specific care coordination activities used by Aging in Place (AIP) nurse care coordinators and home healthcare (HHC) nurses when coordinating care for older community-dwelling adults and suggests a method to quantify care coordination. Methods A care coordination ontology was built based on activities extracted from 11 038 notes labeled with the Omaha Case management category. From the parsed narrative notes of every patient, we mapped the extracted activities to the ontology, from which we computed problem profiles and quantified care coordination for all patients. Results We compared two groups of patients: AIP who received enhanced care coordination (n=217) and HHC who received traditional care (n=691) using 128 135 narratives notes. Patients were tracked from the time they were admitted to AIP or HHC until they were discharged. We found that patients in AIP received a higher dose of care coordination than HHC in most Omaha problems, with larger doses being given in AIP than in HHC in all four Omaha categories. Conclusions ‘Communicate’ and ‘manage’ activities are widely used in care coordination. This confirmed the expert hypothesis that nurse care coordinators spent most of their time communicating about their patients and managing problems. Overall, nurses performed care coordination in both AIP and HHC, but the aggregated dose across Omaha problems and categories is larger in AIP. PMID:25324557

Effects of structures of bidentate Schiff base type bonded-ligands derived from benzaldehyde on the photoluminescence performance of polymer-rare earth complexes.

PubMed

Gao, Baojiao; Zhang, Liqin; Zhang, Dandan

2018-02-07

Two kinds of bidentate Schiff base ligands derived from benzaldehyde, benzaldehyde/m-aminophenol (BAMA) type and benzaldehyde/glutamic acid (BAGL) type ligands, were synchronously synthesized and bonded on the backbone of polysulfone (PSF) through molecular design and by polymer reactions, and two functional polymers, PSF-BAMA and PSF-BAGL, were obtained. Then two series of novel luminescent Schiff base-type polymer-rare earth complexes were prepared via coordination reactions. In this work, the effects of the structures of the bonded ligands on the photoluminescence performance of the complexes were investigated in detail, and for the different photophysical properties of the prepared complexes, relevant theoretical explanations were given. The experimental results show that the bonded ligand BAMA can strongly sensitize the fluorescence emission of Eu(iii) ions, and the binary complex PSF-(BAMA) 3 -Eu(iii) emits strong red fluorescence under UV light. The reason for this lies in the fact that a larger conjugate π-bond system is contained in the structure of BAMA, and so the triplet state of BAMA can be matched with the resonant energy level of the Eu(iii) ion. While the bonded ligand BAGL can effectively sensitize the fluorescence emission of Tb(iii) ions, the binary complex PSF-(BAGL) 3 -Tb(iii) exhibits very strong green fluorescence under UV light. The reason is that a smaller conjugate π-bond system is contained in the structure of BAGL and there is a good energy level matching between the triplet state of BAGL and the resonant energy level of the Tb(iii) ion. The fluorescence intensities of the two ternary complexes, PSF-(BAMA) 3 -Eu(iii)-(Phen) 1 (phenanthroline, Phen) and PSF-(BAGL) 3 -Tb(iii)-(Phen) 1 , are much stronger than that of the corresponding binary complex because Phen as the second ligand has two effects, the effect of synergistic coordination with the first ligand and the effect of replacing the coordinated water around the central ion, and it has been confirmed by fluorescence spectroscopy and thermogravimetric analysis.

Optical, thermal and electrical properties of polybenzimidazoles derived from substituted benzimidazoles

NASA Astrophysics Data System (ADS)

Anand, Siddeswaran; Muthusamy, Athianna

2017-11-01

Three benzimidazole monomers synthesized by condensing various substituted phenolic aldehydes with 4-methylphenylenediamine were converted in to polymers by oxidative polycondensation. The structure of the monomers and polymers were confirmed by various spectroscopic techniques. Electronic distribution of molecular frontier orbitals and optimized geometries of monomers were calculated by Gaussian 09 package. The spectral results showed that the repeating units are connected through both Csbnd C and Csbnd Osbnd C linkages. Both polymers and monomers are showing good fluorescence emission in blue region. The electrical conductivity of I2 doped PBIs was measured using two point probe technique. The conductivities of PBIs were compared on the basis of the charge densities obtained from Huckel method on imidazole nitrogen which is involved in iodine coordination. The conductivity of polymers increases with increase in iodine vapour contact time. The dielectric properties of the synthesized polymers have been investigated at different temperature and frequency. Among the PBIs, PBIOP is having greater thermal stability and is shown by high carbines residues of around 50% at 500 °C in thermogravimetric analysis.

Effect of concentration of molecular crowder on the unfolding force distribution: emergence of a long tail

NASA Astrophysics Data System (ADS)

Kumar, Sanjiv; Singh, Amit Raj; Giri, Debaprasad; Kumar, Sanjay

2017-03-01

We investigate the force induced unfolding transitions of a polymer in presence of crowding particles over a wide range of conditions. The polymer conformations are specified by the reaction coordinate i.e. end-to-end distance and the quality of the solvent. Crowding distribution is obtained through the percolation process, which gives rise to a distribution of clusters of different shapes and sizes starting from isolated disorder sites up to clusters with an extent spanning the entire system. It was shown here that the polymer structures are altered by such distributions and induces an array of structural changes in the form of intermediate states. It was found that the mechanical stability of polymer was insensitive at lower concentration, but increases at higher concentration. This is in accordance with experiments. Exact results based on a short polymer revealed that there is emergence of a long tail in the unfolding force distributions. This is less visible at lower concentration, but has significant contribution at higher concentration. This important feature either was overlooked or not explored so far, and therefore, needs further investigation.

Aggregate-mediated charge transport in ionomeric electrolytes

NASA Astrophysics Data System (ADS)

Lu, Keran; Maranas, Janna; Milner, Scott

Polymers such PEO can conduct ions, and have been studied as possible replacements for organic liquid electrolytes in rechargeable metal-ion batteries. More generally, fast room-temperature ionic conduction has been reported for a variety of materials, from liquids to crystalline solids. Unfortunately, polymer electrolytes generally have limited conductivity; these polymers are too viscous to have fast ion diffusion like liquids, and too unstructured to promote cooperative transport like crystalline solids. Ionomers are polymer electrolytes in which ionic groups are covalently bound to the polymer backbone, neutralized by free counterions. These materials also conduct ions, and can exhibit strong ionic aggregation. Using coarse-grained molecular dynamics, we explore the forces driving ionic aggregation, and describe the role ion aggregates have in mediating charge transport. The aggregates are string-like such that ions typically have two neighbors. We find ion aggregates self-assemble like worm-like micelles. Excess charge, or free ions, occasionally coordinate with aggregates and are transported along the chain in a Grotthuss-like mechanism. We propose that controlling ionomer aggregate structure through materials design can enhance cooperative ion transport.

Star PolyMOCs with Diverse Structures, Dynamics, and Functions by Three-Component Assembly

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Yufeng; Gu, Yuwei; Keeler, Eric G.

2016-12-05

We report star polymer metal–organic cage (polyMOC) materials whose structures, mechanical properties, functionalities, and dynamics can all be precisely tailored through a simple three-component assembly strategy. The star polyMOC network is composed of tetra-arm star polymers functionalized with ligands on the chain ends, small molecule ligands, and palladium ions; polyMOCs are formed via metal–ligand coordination and thermal annealing. The ratio of small molecule ligands to polymer-bound ligands determines the connectivity of the MOC junctions and the network structure. The use of large M12L24 MOCs enables great flexibility in tuning this ratio, which provides access to a rich spectrum of materialmore » properties including tunable moduli and relaxation dynamics.« less

Structure-induced switching of interpolymer adhesion at a solid-polymer melt interface.

PubMed

Jiang, Naisheng; Sen, Mani; Zeng, Wenduo; Chen, Zhizhao; Cheung, Justin M; Morimitsu, Yuma; Endoh, Maya K; Koga, Tadanori; Fukuto, Masafumi; Yuan, Guangcui; Satija, Sushil K; Carrillo, Jan-Michael Y; Sumpter, Bobby G

2018-02-14

Here we report a link between the interfacial structure and adhesive property of homopolymer chains physically adsorbed (i.e., via physisorption) onto solids. Polyethylene oxide (PEO) was used as a model and two different chain conformations of the adsorbed polymer were created on silicon substrates via the well-established Guiselin's approach: "flattened chains" which lie flat on the solid and are densely packed, and "loosely adsorbed polymer chains" which form bridges jointing up nearby empty sites on the solid surface and cover the flattened chains. We investigated the adhesion properties of the two different adsorbed chains using a custom-built adhesion testing device. Bilayers of a thick PEO overlayer on top of the flattened chains or loosely adsorbed chains were subjected to the adhesion test. The results revealed that the flattened chains do not show any adhesion even with the chemically identical free polymer on top, while the loosely adsorbed chains exhibit adhesion. Neutron reflectivity experiments corroborated that the difference in the interfacial adhesion is not attributed to the interfacial brodening at the free polymer-adsorbed polymer interface. Instead, coarse-grained molecular dynamics simulation results suggest that the tail parts of the loosely adsorbed chains act as "connector molecules", bridging the free chains and substrate surface and improving the interfacial adhesion. These findings not only shed light on the structure-property relationship at the interface, but also provide a novel approach for developing sticking/anti-sticking technologies through precise control of the interfacial polymer nanostructures.

A supramolecular Tröger's base derived coordination zinc polymer for fluorescent sensing of phenolic-nitroaromatic explosives in water† †Electronic supplementary information (ESI) available: Spectroscopic (multinuclear NMR, IR HRMS) characterizations, optimized structure, TGA, powder diffraction and fluorescence titration profiles. See DOI: 10.1039/c6sc04367d Click here for additional data file.

PubMed Central

Dabadie, Charlyne; Byrne, Kevin; Savyasachi, Aramballi J.; Umadevi, Deivasigamani; Schmitt, Wolfgang; Kitchen, Jonathan A.

2017-01-01

A V-Shaped 4-amino-1,8-napthalimide derived tetracarboxylic acid linker (L; bis-[N-(1,3-benzenedicarboxylic acid)]-9,18-methano-1,8-naphthalimide-[b,f][1,5]diazocine) comprising the Tröger's base (TB) structural motif was rationally designed and synthesised to access a nitrogen-rich fluorescent supramolecular coordination polymer. By adopting the straight forward precipitation method, a new luminescent nanoscale Zn(ii) coordination polymer (TB-Zn-CP) was synthesized in quantitative yield using Zn(OAc)2·2H2O and tetraacid linker L (1 : 0.5) in DMF at room temperature. The phase-purity of as-synthesised TB-Zn-CP was confirmed by X-ray powder diffraction analysis, infra-red spectroscopy, and elemental analysis. Thermogravimetric analysis suggests that TB-Zn-CP is thermally stable up to 330 °C and the morphological features of TB-Zn-CP was analysed by SEM and AFM techniques. The N2 adsorption isotherm of thermally activated TB-Zn-CP at 77 K revealed a type-II reversible adsorption isotherm and the calculated Brunauer–Emmett–Teller (BET) surface area was found to be 72 m2 g–1. Furthermore, TB-Zn-CP displayed an excellent CO2 uptake capacity of 76 mg g–1 at 273 K and good adsorption selectivity for CO2 over N2 and H2. The aqueous suspension of as-synthesized TB-Zn-CP showed strong green fluorescence (λ max = 520 nm) characteristics due to the internal-charge transfer (ICT) transition and was used as a fluorescent sensor for the discriminative sensing of nitroaromatic explosives. The aqueous suspension of TB-Zn-CP showed the largest quenching responses with high selectivity for phenolic-nitroaromatics (4-NP, 2,4-DNP and PA) even in the concurrent presence of other potentially competing nitroaromatic analytes. The fluorescence titration studies also provide evidence that TB-Zn-CP detects picric acid as low as the parts per billion (26.3 ppb) range. Furthermore, the observed fluorescence quenching responses of TB-Zn-CP towards picric acid were highly reversible. The highly selective fluorescence quenching responses including the reversible detection efficiency make the nanoscale coordination polymer TB-Zn-CP a potential material for the discriminative fluorescent sensing of nitroaromatic explosives. PMID:28572910

Synthesis, crystal structure and magnetic characterization of metal(II) coordination polymers based on 2-carboxyethylphosphonic acid and 1,10-phenanthroline (metal=Cu, Co, Cd)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fernandez-Zapico, Eva; Montejo-Bernardo, Jose Manuel; D'Vries, Richard

2011-12-15

Three non-isostructural metal(II) coordination polymers (metal=copper, cobalt, cadmium) were synthesized under the same mild hydrothermal conditions (T=408 K) by mixture of the corresponding metal acetate with 2-carboxyethylphosphonic acid and 1,10-phenanthroline (1:1:1 M ratio) and their structures were determined by single-crystal X-ray diffraction. Cu{sub 2}(HO{sub 3}PCH{sub 2}CH{sub 2}COO){sub 2}(C{sub 12}H{sub 8}N{sub 2}){sub 2}(H{sub 2}O){sub 2} and Cd{sub 2}(HO{sub 3}PCH{sub 2}CH{sub 2}COO){sub 2}(C{sub 12}H{sub 8}N{sub 2}){sub 2} are triclinic (space group P-1) with a=7.908(5) A, b=10.373(5) A, c=11.515(5) A, {alpha}=111.683(5) Degree-Sign , {beta}=95.801(5) Degree-Sign , {gamma}=110.212(5) Degree-Sign (T=120 K), and a=8.162(5) A, b=9.500(5) A, c=11.148(5) A, {alpha}=102.623(5) Degree-Sign , {beta}=98.607(5) Degree-Sign ,more » {gamma}=113.004(5) Degree-Sign (T=293 K), respectively. In contrast, [Co{sub 2}(HO{sub 3}PCH{sub 2}CH{sub 2}COO){sub 2}(C{sub 12}H{sub 8}N{sub 2}){sub 2}({mu}-OH{sub 2})](H{sub 2}O) is orthorhombic (space group Pbcn) with a=21.1057(2) A, b=9.8231(1) A, c=15.4251(1) A (T=120 K). For these three compounds, structural features, including H-bond network and the {pi}-{pi} stacking interactions, and thermal stability are reported and discussed. None of the materials present a long-range magnetic order in the range of temperatures investigated from 300 K down to 1.8 K. - Graphical abstract: In same synthetic conditions, both the chemical and structural features of three transition metal(II) coordination polymers based on 2-carboxyethylphosphonate and 1-10 Prime -phenanthroline are influenced by the metal cation characteristics, leading to non-homologous materials with different properties, which show the high chemical versatility of this interesting system. Highlights: Black-Right-Pointing-Pointer Non-isostructural metal coordination polymers were synthesized under mild hydrothermal conditions. Black-Right-Pointing-Pointer Ligand's flexibility provides the opportunity to design compounds with tailored properties. Black-Right-Pointing-Pointer Structural changes in the secondary building units are induced by metal features.« less

Hybrid nanocomposites of CdSe nanocrystals distributed in complexing thiophene-based copolymers.

PubMed

Aldakov, Dmitry; Jiu, Tonggang; Zagorska, Malgorzata; de Bettignies, Rémi; Jouneau, Pierre-Henri; Pron, Adam; Chandezon, Frédéric

2010-07-21

Two types of conjugated polymers were prepared with the goal to blend them with rod-like CdSe nanocrystals. The polymers of the first type were synthesized through copolymerization of 3-octylthiophene and 3-methylene-ethylcarboxylate-thiophene to give polythiophene with solubilizing alkyl groups and methylene ester functional groups (PE series). Post-polymerization hydrolysis of the ester type polymers yielded acid-type ones (PA series). Photoluminescence (PL) quenching in these polymers induced by their titration with nanocrystals solution was chosen as a measure of the polymer-nanocrystal interactions. PL of polyacids turned out to be more efficiently quenched as compared to the case of polymers with ester groups which was interpreted as an indication of better electronic communication between the hybrid components. Infrared (IR) spectroscopy confirmed efficient coordination of the carboxylic groups to CdSe. Voltammetric studies combined with UV-vis spectroelectrochemistry enabled the determination of energy levels alignment of the molecular composite components which turned out to be of staggered type-appropriate for photovoltaic applications. The obtained blends of polyacids with CdSe nanocrystals, when studied by transmission electron microscopy (TEM), revealed the presence of an interpenetrating network in which nanorods were homogeneously distributed within the polymer matrix without any indication of agglomerates formation both on the film surface and in the cross-section. Blends with polymers containing ester groups were less homogeneous which could be explained by weaker polymer-nanocrystals interactions. Photovoltaic cells based on these hybrid materials are also discussed.

Creating a Smart Classroom

ERIC Educational Resources Information Center

Domermuth, David

2005-01-01

This article provides a description of an affordable, smart classroom system that was built for the Technology Department at Appalachian State University in Boone, NC. In the hope that other educators might find his department's experience useful, this author, David Domermuth (the department's coordinator of manufacturing) describes the system,…

Construction of digital core by adaptive porosity method

NASA Astrophysics Data System (ADS)

Xia, Huifen; Liu, Ting; Zhao, Ling; Sun, Yanyu; Pan, Junliang

2017-05-01

The construction of digital core has its unique advantages in the study of water flooding or polymer flooding oil displacement efficiency. The frequency distribution of pore size is measured by mercury injection experiment, the coordination number by CT scanning method, and the wettability data by imbibition displacement was measured, on the basis of considering the ratio of pore throat ratio and wettability, the principle of adaptive porosity is used to construct the digital core. The results show that the water flooding recovery, the degree of polymer flooding and the results of the Physical simulation experiment are in good agreement.

Disulfide-Bridged (Mo3S11) Cluster Polymer: Molecular Dynamics and Application as Electrode Material for a Rechargeable Magnesium Battery.

PubMed

Truong, Quang Duc; Kempaiah Devaraju, Murukanahally; Nguyen, Duc N; Gambe, Yoshiyuki; Nayuki, Keiichiro; Sasaki, Yoshikazu; Tran, Phong D; Honma, Itaru

2016-09-14

Exploring novel electrode materials is critical for the development of a next-generation rechargeable magnesium battery with high volumetric capacity. Here, we showed that a distinct amorphous molybdenum sulfide, being a coordination polymer of disulfide-bridged (Mo3S11) clusters, has great potential as a rechargeable magnesium battery cathode. This material provided good reversible capacity, attributed to its unique structure with high flexibility and capability of deformation upon Mg insertion. Free-terminal disulfide moiety may act as the active site for reversible insertion and extraction of magnesium.

Synthesis, characterization and solid state electrical properties of 1-D coordination polymer of the type [Cu{sub x}Ni{sub 1-x}(dadb){center_dot}yH{sub 2}O]{sub n}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prasad, R.L., E-mail: rlpjc@yahoo.co.in; Kushwaha, A.; Shrivastava, O.N.

2012-12-15

New heterobimetallic complexes [Cu{sub x}Ni{sub 1-x}(dadb){center_dot}yH{sub 2}O]{sub n} {l_brace}where dadb=2,5-Diamino-3,6-dichloro-1,4-benzoquinone (1); x=1 (2), 0.5 (4), 0.25 (5), 0.125 (6), 0.0625 (7) and 0 (3); y=2; n=degree of polymerization{r_brace} were synthesized and characterized. Heterobimetallic complexes show normal magnetic moments, whereas, monometallic complexes exhibit magnetic moments less than the value due to spin only. Thermo-gravimetric analysis shows that degradation of the ligand dadb moiety is being controlled by the electronic environment of the Cu(II) ions in preference over Ni(II) in heterobimetallic complexes. Existence of the mixed valency/non-integral oxidation states of copper and nickel metal ions in the complex 4 has been attributedmore » from magnetic moment and ESR spectral results. Solid state dc electrical conductivity of all the complexes was investigated. Monometallic complexes were found to be semiconductors, whereas heterobimetallic coordination polymer 4 was found to exhibit metallic behaviour. Existence of mixed valency/ non-integral oxidation state of metal ions seems to be responsible for the metallic behaviour. - Graphical abstract: Contrast to the semiconductor monometallic complexes 2 and 3, the heterobimetallic complex 4 exhibits metallic behaviour attributed to the mixed valency/non-integral oxidation state of the metal ions concluded from magnetic and ESR spectral studies. Highlights: Black-Right-Pointing-Pointer 1-D coordination compounds of the type Cu{sub x}Ni{sub 1-x}(dadb){center_dot}yH{sub 2}O were synthesized and characterized. Black-Right-Pointing-Pointer Thermal degradation of the complexes provides an indication of long range electronic communication between metal to ligand. Black-Right-Pointing-Pointer On inclusion of Ni(II) into 1-D coordination polymer of Cu(II). (a) Cu(II) and Ni(II) ions exhibit non-integral oxidation state. (b) resulting heterobimetallic complex 4 exhibits metallic behaviour at all temperature range of the present study whereas monometallic complexes are semiconductor.« less

Cortical basis of communication: local computation, coordination, attention.

PubMed

Alexandre, Frederic

2009-03-01

Human communication emerges from cortical processing, known to be implemented on a regular repetitive neuronal substratum. The supposed genericity of cortical processing has elicited a series of modeling works in computational neuroscience that underline the information flows driven by the cortical circuitry. In the minimalist framework underlying the current theories for the embodiment of cognition, such a generic cortical processing is exploited for the coordination of poles of representation, as is reported in this paper for the case of visual attention. Interestingly, this case emphasizes how abstract internal referents are built to conform to memory requirements. This paper proposes that these referents are the basis for communication in humans, which is firstly a coordination and an attentional procedure with regard to their congeners.

Metal-organometallic polymers and frameworks derived from facially metalated arylcarboxylates

NASA Astrophysics Data System (ADS)

Kumalah Robinson, Sayon A.

The interest in coordination polymers, also known as metal-organic frameworks, has risen drastically over the past 2 decades. In this time, the field has matured and given rise to a diverse range of crystalline structures possessing various functionalities. Coordination polymers are typically formed from the self assembly of metal ions which serve as nodes and organic ligands which act as bridges. By the careful selection of the organic ligand and the metal ion, the overall physical properties of the material may be tuned. In this work, the use of organometallic bridging ligands are explored using facially metalated aryl carboxylates ligands to synthesize metal-organometallic frameworks (MOMFs). Therefore, with the aim of synthesizing [CpM]+-functionalized (M = FeII, RuII; Cp = cyclopentadienyl) coordination polymers and metal organic frameworks, various [CpFe]+and [CpRu] + functionalized aryl carboxylates were synthesized and characterized. In particular, the [CpFe]+-functionalized benzoic, terephthalic and trimesic acids as well as the [CpRu]+-functionalized terephthalic acid were made. Using the [CpFe]+ complexes of the benzoic and terephthalic acid as bridging ligands, a number of 1D and 2D coordination polymers were synthesized. For instance, the reaction of [CpFe]+-functionalized benzoic acid with CdCl2 yielded the 1D chain of [Cd(benzoate)Cl 2]˙H2O whilst the reaction of [CpFe]+-functionalized terephthalic acid with Cu(NO3)2˙6H2O yielded a 2D square grid sheet. Using the [CpFe]+-functionalized terephthalic acid, a series of polymorphic, 3D metal-organometallic frameworks of the general formula [M3(terephthalate)4(mu-H2O)2(H 2O)2][NO3]2˙xsolvent (M = Co II, NiII ; solvent = EtOH, DMF, H2O) were synthesized and fully characterized. The polymorphic nature of these frameworks may be attributed to the different orientations that the [CpFe]+ moiety may adapt within the cavities in the 3D frameworks. The selectivity of the desolvated forms of the polymorphs for various alcohols was also probed. A framework having the same 3D topology but slightly different composition as the polymorphic frameworks of [M3(terephthalate)4(mu-H 2O)2(H2O)2][NO3]2˙ xsolvent was obtained using MnBr2˙4H2O. The solvothermal reaction of [CpFe]+-functionalized terephthalic acid and Co(NO3)2˙6H2O afforded the first microporous metal-organometallic phosphate. This 3D framework formed a cubic, 12-connected face centered net featuring a novel dodecanuclear truncated tetrahedral node consisting of [CpFe(terephthalate)]+, CoII, F- and phosphate ions. Lastly, the [CpFe]+-functionalized terephthalic acid was successfully reticulated into the MIL-88 and MIL 53 framework topologies indicating that the metalated ligand may be used to synthesis both known and novel 3D metal organic frameworks.

Crystal structure of dipotassium N-carbodi­thio­ato-l-prolinate trihydrate

PubMed Central

2017-01-01

The mol­ecular and crystal structure of the l-proline-derived di­thio­carbamate–carboxyl­ate compound poly[tri-μ-aqua-(μ-2-carboxyl­atopyrrolidine-1-carbodi­thio­ato)dipotassium], [K2(C6H7NO2S2)(H2O)3]n or K2(SSC–NC4H7–COO)·3H2O, has been determined. The di­thio­carbamate moiety displays a unique coordination mode, comprising a ‘side-on’ π-coordinated K+ cation besides a commonly σ-chelated K+ cation. By bridging coordination of the CSS group, COO group and water mol­ecules, the K+ cations are linked into a two-dimensional coordination polymer extending parallel to the ab plane. These layers are again inter­connected by O—H⋯S hydrogen bonds. PMID:28932478

Dependence of crystal size on the catalytic performance of a porous coordination polymer.

PubMed

Kiyonaga, Tomokazu; Higuchi, Masakazu; Kajiwara, Takashi; Takashima, Yohei; Duan, Jingui; Nagashima, Kazuro; Kitagawa, Susumu

2015-02-14

Submicrosized MOF-76(Yb) exhibits a higher catalytic performance for esterification than microsized MOF-76(Yb). Control of the crystal size of porous heterogeneous catalysts, such as PCP/MOFs, offers a promising approach to fabricating high-performance catalysts based on accessibility to the internal catalytic sites.

Probing hydrogen and halogen-oxo interactions in uranyl coordination polymers: a combined crystallographic and computational study

DOE PAGES

Carter, Korey P.; Kalaj, Mark; Kerridge, Andrew; ...

2018-01-01

Four uranyl compounds containing either benzoic acid ( 1 ), m -chlorobenzoic acid ( 2 ), m -bromobenzoic acid ( 3 ), or m -iodobenzoic acid ( 4 ) are described, and the latter two compounds are used to probe non-covalent interaction strengths via structural, vibrational, and computational means.

Molecular weaving via surface-templated epitaxy of crystalline coordination networks.

PubMed Central

Wang, Zhengbang; Błaszczyk, Alfred; Fuhr, Olaf; Heissler, Stefan; Wöll, Christof; Mayor, Marcel

2017-01-01

One of the dream reactions in polymer chemistry is the bottom-up, self-assembled synthesis of polymer fabrics, with interwoven, one-dimensional fibres of monomolecular thickness forming planar pieces of textiles. We have made a major step towards realizing this goal by assembling sophisticated, quadritopic linkers into surface-mounted metal-organic frameworks. By sandwiching these quadritopic linkers between sacrificial metal-organic framework thin films, we obtained multi-heteroepitaxial, crystalline systems. In a next step, Glaser–Hay coupling of triple bonds in the quadritopic linkers yields linear, interwoven polymer chains. X-ray diffraction studies revealed that this topochemical reaction leaves the MOF backbone completely intact. After removing the metal ions, the textile sheets can be transferred onto different supports and imaged using scanning electron microscopy and atomic-force microscopy. The individual polymer strands forming the two-dimensional textiles have lengths on the order of 200 nm, as evidenced by atomic-force microscopy images recorded from the disassembled textiles. PMID:28198388

Enhancing Cation Diffusion and Suppressing Anion Diffusion via Lewis-Acidic Polymer Electrolytes.

PubMed

Savoie, Brett M; Webb, Michael A; Miller, Thomas F

2017-02-02

Solid polymer electrolytes (SPEs) have the potential to increase both the energy density and stability of lithium-based batteries, but low Li + conductivity remains a barrier to technological viability. SPEs are designed to maximize Li + diffusivity relative to the anion while maintaining sufficient salt solubility. It is thus remarkable that poly(ethylene oxide) (PEO), the most widely used SPE, exhibits Li + diffusivity that is an order of magnitude smaller than that of typical counterions at moderate salt concentrations. We show that Lewis-basic polymers like PEO favor slow cation and rapid anion diffusion, while this relationship can be reversed in Lewis-acidic polymers. Using molecular dynamics, polyboranes are identified that achieve up to 10-fold increases in Li + diffusivities and significant decreases in anion diffusivities, relative to PEO in the dilute-ion regime. These results illustrate a general principle for increasing Li + diffusivity and transference number with chemistries that exhibit weaker cation and stronger anion coordination.

Preparation and luminescent properties of the novel polymer-rare earth complexes composed of Poly(ethylene-co-acrylic acid) and Europium ions

NASA Astrophysics Data System (ADS)

Wu, Yuewen; Hao, Haixia; Wu, Qingyao; Gao, Zihan; Xie, Hongde

2018-06-01

A series of novel polymer-rare earth complexes with Eu3+ ions have been synthesized and investigated successfully, including the binary complexes containing the single ligand poly(ethylene-co-acrylic acid) (EAA) and the ternary complexes using 1,10-phenanthroline (phen), dibenzoylmethane (DBM) or thenoyltrifluoroacetone (TTA) as the second ligand. Their structures have been characterized by Fourier transform infrared spectroscopy (FT-IR), elemental analysis and X-ray diffraction (XRD), which confirm that both EAA and small molecules participate in the coordination reaction with rare earth ions, and they can disperse homogeneously in the polymer matrixes. Both ultraviolet-visible (UV-vis) absorption and photoluminescence tests for the complexes have been recorded. The relationship between fluorescence intensity of polymer-rare earth complexes and the quantity of ligand EAA has been studied and discussed. The films casted from the complexes solution can emit strong characteristic red light under UV light excitation. All these results suggest that the complexes possess potential application as luminescent materials.

Superhydrophobic and polymer drag reduction in turbulent Taylor-Couette flow

NASA Astrophysics Data System (ADS)

Rajappan, Anoop; McKinley, Gareth H.

2017-11-01

We use a custom-built Taylor-Couette apparatus (radius ratio η = 0.75) to study frictional drag reduction by dilute polymer solutions and superhydrophobic (SH) surfaces in turbulent flows for 15000 < Re < 86000 . By monitoring the torque-speed scaling we show that the swirling flow becomes fully turbulent above Re = 15000 and we focus on measurements in this regime. By applying SH coatings on the inner cylinder, we can evaluate the drag reducing performance of the coating and calculate the effective slip length in turbulent flow using a suitably modified Prandtl-von Kármán analysis. We also investigate drag reduction by dilute polymer solutions, and show that natural biopolymers from plant mucilage can be an inexpensive and effective alternative to synthetic polymers in drag reduction applications, approaching the same maximum drag reduction asymptote. Finally we explore combinations of the two methods - one arising from wall slip and the other due to changes in turbulence dynamics in the bulk flow - and find that the two effects are not additive; interestingly, the effectiveness of polymer drag reduction is drastically reduced in the presence of an SH coating on the wall. This study was financially supported by the Office of Naval Research (ONR) through Contract No. 3002453814.

A hierarchical classification approach for recognition of low-density (LDPE) and high-density polyethylene (HDPE) in mixed plastic waste based on short-wave infrared (SWIR) hyperspectral imaging

NASA Astrophysics Data System (ADS)

Bonifazi, Giuseppe; Capobianco, Giuseppe; Serranti, Silvia

2018-06-01

The aim of this work was to recognize different polymer flakes from mixed plastic waste through an innovative hierarchical classification strategy based on hyperspectral imaging, with particular reference to low density polyethylene (LDPE) and high-density polyethylene (HDPE). A plastic waste composition assessment, including also LDPE and HDPE identification, may help to define optimal recycling strategies for product quality control. Correct handling of plastic waste is essential for its further "sustainable" recovery, maximizing the sorting performance in particular for plastics with similar characteristics as LDPE and HDPE. Five different plastic waste samples were chosen for the investigation: polypropylene (PP), LDPE, HDPE, polystyrene (PS) and polyvinyl chloride (PVC). A calibration dataset was realized utilizing the corresponding virgin polymers. Hyperspectral imaging in the short-wave infrared range (1000-2500 nm) was thus applied to evaluate the different plastic spectral attributes finalized to perform their recognition/classification. After exploring polymer spectral differences by principal component analysis (PCA), a hierarchical partial least squares discriminant analysis (PLS-DA) model was built allowing the five different polymers to be recognized. The proposed methodology, based on hierarchical classification, is very powerful and fast, allowing to recognize the five different polymers in a single step.

Synthesis and characterization of donor-acceptor copolymers carrying triphenylamine units for photovoltaic applications

NASA Astrophysics Data System (ADS)

Neumann, Katharina; Thelakkat, Mukundan

2012-09-01

The synthesis and analysis of solution processable polymers for organic solar cells is crucial for innovative solar cell technologies such as printing processes. In the field of donor materials for photovoltaic applications, polymers based on tetraphenylamine (TPA) are well known hole conducting materials. Here, we synthesized two conjugated TPA containing copolymers via Suzuki polycondensation. We investigated the tuning of the energy levels of the TPA based polymers by two different concepts. Firstly, we introduced an acceptor unit in the side chain. The main-chain of this copolymer was built from TPA units. The resulting copolymer 2-(4-((4'-((4-(2-ethylhexyloxy)phenyl)(paratolyl) amino)biphenyl-4-yl)(para-tolyl)amino)benzylidene) malononitrile P1 showed a broader absorption up to 550 nm. Secondly, we used a donor-acceptor concept by synthesizing a copolymer with alternating electron donating TPA and electron withdrawing Thieno[3,4-b]thiophene ester units. Consequently, the absorption maximum in the copolymer octyl-6-(4-((4-(2-ethylhexyloxy)phenyl)(p-tolyl)amino)phenyl)-4-methylthieno[3,4-b]thiophene-2-carboxylate P2 was red shifted to 580 nm. All three polymers showed high thermal stability. By UV-vis and Cyclic voltammetry measurements the optical and electrochemical properties of the polymers were analyzed.

Research and simulation of the decoupling transformation in AC motor vector control

NASA Astrophysics Data System (ADS)

He, Jiaojiao; Zhao, Zhongjie; Liu, Ken; Zhang, Yongping; Yao, Tuozhong

2018-04-01

Permanent magnet synchronous motor (PMSM) is a nonlinear, strong coupling, multivariable complex object, and transformation decoupling can solve the coupling problem of permanent magnet synchronous motor. This paper gives a permanent magnet synchronous motor (PMSM) mathematical model, introduces the permanent magnet synchronous motor vector control coordinate transformation in the process of modal matrix inductance matrix transform through the matrix related knowledge of different coordinates of diagonalization, which makes the coupling between the independent, realize the control of motor current and excitation the torque current coupling separation, and derived the coordinate transformation matrix, the thought to solve the coupling problem of AC motor. Finally, in the Matlab/Simulink environment, through the establishment and combination between the PMSM ontology, coordinate conversion module, built the simulation model of permanent magnet synchronous motor vector control, introduces the model of each part, and analyzed the simulation results.

Self-Positioned Nanosized Mask for Transparent and Flexible Ferroelectric Polymer Nanodiodes Array.

PubMed

Hyun, Seung; Kwon, Owoong; Choi, Chungryong; Vincent Joseph, Kanniyambatti L; Kim, Yunseok; Kim, Jin Kon

2016-10-12

High density arrays of ferroelectric polymer nanodiodes have gained strong attention for next-generation transparent and flexible nonvolatile resistive memory. Here, we introduce a facile and innovative method to fabricate ferroelectric polymer nanodiode array on an ITO-coated poly(ethylene terephthalate) (PET) substrate by using block copolymer self-assembly and oxygen plasma etching. First, polystyrene-block-poly(2-vinylpyridine) copolymer (PS-b-P2VP) micelles were spin-coated on poly(vinylidene fluoride-ran-trifluoroethylene) copolymer (P(VDF-TrFE)) film/ITO-coated PET substrate. After the sample was immersed in a gold precursor (HAuCl 4 ) containing solution, which strongly coordinates with nitrogen group in P2VP, oxygen plasma etching was performed. During the plasma etching, coordinated gold precursors became gold nanoparticles (GNPs), which successfully acted as self-positioned etching mask to fabricate a high density array of P(VDF-TrFE)) nanoislands with GNP at the top. Each nanoisland shows clearly individual diode property, as confirmed by current-voltage (I-V) curve. Furthermore, due to the transparent and flexible nature of P(VDF-TrFE)) nanoisland as well as the substrate, the P(VDF-TrFE) nanodiode array was highly tranparent, and the diode property was maintained even after a large number of bendings (for instance, 1000 times). The array could be used as the next-generation tranparent and flexible nonvolatile memory device.

Conjugated polymer with carboxylate groups-Hg2 + system as a turn-on fluorescence probe for label-free detection of cysteine-containing compounds

NASA Astrophysics Data System (ADS)

Mi, Hongyu; Guan, Mingming; Liu, Jilin; Shan, Hongyan; Fei, Qiang; Huan, Yanfu; Feng, Guodong

2017-04-01

In this work, a turn on fluorescent sensor, based on Hg2 + coordination conjugated polymer, was developed to detect cysteine-containing compounds. The fluorescence of conjugated polymer (poly(2,5-bis (sodium 4-oxybutyrate) -1,4 - phenylethynylene-alt-1,4-phenyleneethynylene; PPE-OBS) would be quenched by Hg2 + because of the coordination-induced aggregation and electron transfers of PPE-OBS toward Hg2 +. When there were some cysteine-containing compounds in PPE-OBS-Hg2 + system, the fluorescence of PPE-OBS would be recovered. It indicated that the PPE-OBS-Hg2 + system could be used to detect cysteine-containing compounds. Under the optimized conditions, the experiment results showed that there were particularly linear range, high sensitivity and selectivity over other amino acids. The limit of detection (LOD) of cysteine (Cys), homocysteine (Hcy) and glutathione (GSH) were 0.725 μmol L- 1, 0.982 μmol L- 1 and 1.21 μmol L- 1 by using this sensor. In addition, Cys standard recovery in several green tea drink and honey samples was also demonstrated. The recovery of Cys was range from 96.3 to 105.0% and RSD was less than 3.25%. The satisfactory results demonstrated that the proposed method could be as a potential fluorescent method for determining cysteine-containing compounds in real samples.

Space Craft

ERIC Educational Resources Information Center

Demski, Jennifer

2009-01-01

This article discusses how craft innovative architecture is bringing form to the function of 21st-century learning. It describes the construction of New Tech High at Coppell, in Coppell, Texas, which produces an example of how workplace design principles can be coordinated with modern educational goals. The campus was built on the model of New…

78 FR 18321 - International Code Council: The Update Process for the International Codes and Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-26

... for Residential Construction in High Wind Regions. ICC 700: National Green Building Standard The..., coordinated, and necessary to regulate the built environment. Federal agencies frequently use these codes and... International Codes and Standards consist of the following: ICC Codes International Building Code. International...

75 FR 19944 - International Code Council: The Update Process for the International Codes and Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-16

... for Residential Construction in High Wind Areas. ICC 700: National Green Building Standard. The... Codes and Standards that are comprehensive, coordinated, and necessary to regulate the built environment... International Codes and Standards consist of the following: ICC Codes International Building Code. International...

The Discovery of Personal Meaning: Affective Factors in Learning.

ERIC Educational Resources Information Center

Gorrell, Jeffrey

Learner-centered principles espoused by the American Psychological Association (APA) built on research of the last three decades suggest that learning does not simply entail coordinated cognitive processes. These 12 principles portray factors associated with learning as essential parts of the portrayal of learners as active creators of their own…

In-syringe extraction using dissolvable layered double hydroxide-polymer sponges templated from hierarchically porous coordination polymers.

PubMed

Ghani, Milad; Frizzarin, Rejane M; Maya, Fernando; Cerdà, Víctor

2016-07-01

Herein we report the use of cobalt porous coordination polymers (PCP) as intermediates to prepare advanced extraction media based on layered double hydroxides (LDH) supported on melamine polymer foam. The obtained dissolvable Ni-Co LDH composite sponges can be molded and used as sorbent for the in-syringe solid-phase extraction (SPE) of phenolic acids from fruit juices. The proposed sorbent is obtained due to the surfactant-assisted self-assembly of Co(II)/imidazolate PCPs on commercially available melamine foam, followed by the in situ conversion of the PCP into the final dissolvable LDH coating. Advantageous features for SPE are obtained by using PCPs with hierarchical porosity (HPCPs). The LDH-sponge prepared using intermediate HPCPs (HLDH-sponge) is placed in the headspace of a glass syringe, enabling flow-through extraction followed by analyte elution by the dissolution of the LDH coating in acidic conditions. Three phenolic acids (gallic acid, p-hydroxybenzoic acid and caffeic acid) were extracted and quantified using high performance liquid chromatography. Using a 5mL sample volume, the obtained detection limits were 0.15-0.35μgL(-1). The proposed method for the preparation of HLDH-sponges showed a good reproducibility as observed from the intra- and inter-day RSD's, which were <10% for all analytes. The batch-to-batch reproducibility for three different batches of HLDH-sponges was 10.6-11.2%. Enrichment factors of 15-21 were obtained. The HLDH-sponges were applied satisfactorily to the determination of phenolic acids in natural and commercial fruit juices, obtaining relative recoveries among 89.7-95.3%. Copyright © 2016 Elsevier B.V. All rights reserved.

Quantifying care coordination using natural language processing and domain-specific ontology.

PubMed

Popejoy, Lori L; Khalilia, Mohammed A; Popescu, Mihail; Galambos, Colleen; Lyons, Vanessa; Rantz, Marilyn; Hicks, Lanis; Stetzer, Frank

2015-04-01

This research identifies specific care coordination activities used by Aging in Place (AIP) nurse care coordinators and home healthcare (HHC) nurses when coordinating care for older community-dwelling adults and suggests a method to quantify care coordination. A care coordination ontology was built based on activities extracted from 11,038 notes labeled with the Omaha Case management category. From the parsed narrative notes of every patient, we mapped the extracted activities to the ontology, from which we computed problem profiles and quantified care coordination for all patients. We compared two groups of patients: AIP who received enhanced care coordination (n=217) and HHC who received traditional care (n=691) using 128,135 narratives notes. Patients were tracked from the time they were admitted to AIP or HHC until they were discharged. We found that patients in AIP received a higher dose of care coordination than HHC in most Omaha problems, with larger doses being given in AIP than in HHC in all four Omaha categories. 'Communicate' and 'manage' activities are widely used in care coordination. This confirmed the expert hypothesis that nurse care coordinators spent most of their time communicating about their patients and managing problems. Overall, nurses performed care coordination in both AIP and HHC, but the aggregated dose across Omaha problems and categories is larger in AIP. © The Author 2014. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Zwitterionic peptide anchored to conducting polymer PEDOT for the development of antifouling and ultrasensitive electrochemical DNA sensor.

PubMed

Wang, Guixiang; Han, Rui; Su, Xiaoli; Li, Yinan; Xu, Guiyun; Luo, Xiliang

2017-06-15

Zwitterionic peptides were anchored to a conducting polymer of citrate doped poly(3,4-ethylenedioxythiophene) (PEDOT) via the nickel cation coordination, and the obtained peptide modified PEDOT, with excellent antifouling ability and good conductivity, was further used for the immobilization of a DNA probe to construct an electrochemical biosensor for the breast cancer marker BRCA1. The DNA biosensor was highly sensitive (with detection limit of 0.03fM) and selective, and it was able to detect BRCA1 in 5% (v/v) human plasma with satisfying accuracy and low fouling. The marriage of antifouling and biocompatible peptides with conducting polymers opened a new avenue to construct electrochemical biosensors capable of assaying targets in complex biological media with high sensitivity and without biofouling. Copyright © 2016 Elsevier B.V. All rights reserved.

Molecular dynamics simulation of low dielectric constant polymer electrolytes

NASA Astrophysics Data System (ADS)

Wheatle, Bill; Lynd, Nathaniel; Ganesan, Venkat

Recent experimental studies measured the ionic conductivities of a series of poly(glycidyl ether)s with varying neat dielectric constants (ɛ), viscosities (η), and glass transition temperatures (Tg), as hosts for lithium bistrifluoromethanesulfonimide (LiTFSI) salt. In such a context, it was demonstrated that the ionic conductivity of these polymer electrolytes was a function of ɛ rather than Tg or η, suggesting that there may exist regimes in which ionic conductivity is not limited by slow segmental dynamics but rather by low ionic dissociation. Motivated by such results, we used atomistic molecular dynamics to study the structure and transport characteristics of the same set of host polymers. We found that the coordination number of TFSI- about Li+ in the first solvation shell and the total fraction of free ions increased as a function of ɛ, implying the polymer hosts enhanced ion dissociation. In addition, we found that increasing the dielectric constant of the host polymer enhanced self-correlated ion transport, as evidenced by an increase in the diffusion coefficients of each ion species. Overall, we confirmed that limited ion dissociation in low- ɛ polymer electrolyte hosts hampers ionic conductivity. We would like to thank the National Science Foundation Graduate Research Fellowship Program for funding this research endeavor.

Modeling the Coupled Chemo-Thermo-Mechanical Behavior of Amorphous Polymer Networks.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zimmerman, Jonathan A.; Nguyen, Thao D.; Xiao, Rui

2015-02-01

Amorphous polymers exhibit a rich landscape of time-dependent behavior including viscoelasticity, structural relaxation, and viscoplasticity. These time-dependent mechanisms can be exploited to achieve shape-memory behavior, which allows the material to store a programmed deformed shape indefinitely and to recover entirely the undeformed shape in response to specific environmental stimulus. The shape-memory performance of amorphous polymers depends on the coordination of multiple physical mechanisms, and considerable opportunities exist to tailor the polymer structure and shape-memory programming procedure to achieve the desired performance. The goal of this project was to use a combination of theoretical, numerical and experimental methods to investigate themore » effect of shape memory programming, thermo-mechanical properties, and physical and environmental aging on the shape memory performance. Physical and environmental aging occurs during storage and through exposure to solvents, such as water, and can significantly alter the viscoelastic behavior and shape memory behavior of amorphous polymers. This project – executed primarily by Professor Thao Nguyen and Graduate Student Rui Xiao at Johns Hopkins University in support of a DOE/NNSA Presidential Early Career Award in Science and Engineering (PECASE) – developed a theoretical framework for chemothermo- mechanical behavior of amorphous polymers to model the effects of physical aging and solvent-induced environmental factors on their thermoviscoelastic behavior.« less

Relaxation dynamics of a multihierarchical polymer network

NASA Astrophysics Data System (ADS)

Jurjiu, Aurel; Biter, Teodor Lucian; Turcu, Flaviu

2017-01-01

In this work, we study the relaxation dynamics of a multihierarchical polymer network built by replicating the Vicsek fractal in dendrimer shape. The relaxation dynamics is investigated in the framework of the generalized Gaussian structure model by employing both Rouse and Zimm approaches. In the Rouse-type approach, we show the iterative procedure whereby the whole eigenvalue spectrum of the connectivity matrix of the multihierarchical structure can be obtained. Remarkably, the general picture that emerges from both approaches, even though we have a mixed growth algorithm, is that the obtained multihierarchical structure preserves the individual relaxation behaviors of its components. The theoretical findings with respect to the splitting of the intermediate domain of the relaxation quantities are well supported by experimental results.

Conjugated polymer sensors built on pi-extended borasiloxane cages.

PubMed

Liu, Wenjun; Pink, Maren; Lee, Dongwhan

2009-06-24

An efficient 2 + 2 cyclocondensation with dihydroxysilane converted simple arylboronic acids to bifunctional borasiloxane cage molecules, which were subsequently electropolymerized to furnish air-stable thin films. The extended [p,pi]-conjugation that defines the rigid backbone of this new conjugated polymer (CP) motif gives rise to longer-wavelength UV-vis transitions upon oxidative doping, the spectral window and intensity of which can be modified by interaction with Lewis basic reagents. Notably, this boron-containing CP undergoes a rapid and reversible color change from green to orange upon exposure to volatile amine samples under ambient conditions. This direct naked-eye detection scheme can best be explained by invoking the reversible B-N dative bond formation that profoundly influences the p-pi* orbital overlap.

Functional and Multifunctional Polymers: Materials for Smart Structures

NASA Technical Reports Server (NTRS)

Arnold, S.; Pratt, L. M.; Li, J.; Wuagaman, M.; Khan, I. M.

1996-01-01

The ultimate goal of the research in smart structures and smart materials is the development of a new generation of products/devices which will perform better than products/devices built from passive materials. There are a few examples of multilayer polymer systems which function as smart structures, e.g. a synthetic muscle which is a multilayer assembly of a poly(ethylene) layer, a gold layer, and a poly(pyrrole) layer immersed in a liquid electrolyte. Oxidation and reductions of the active pyrrole layer causes the assembly to reversibly deflect and mimic biological muscles. The drawback of such a setup is slow response times and the use of a liquid electrolyte. We have developed multifunctional polymers which will eliminate the use of a liquid electrolyte, and also because the functionalities of the polymers are within a few hundred angstroms, an improved response time to changes in the external field should be possible. Such multifunctional polymers may be classified as the futuristic 'smart materials.' These materials are composed of a number of different functionalities which work in a synergistic fashion to function as a device. The device performs on the application of an external field and such multifunctional polymers may be scientifically labeled as 'field responsive polymers.' Our group has undertaken a systematic approach to develop functional and multifunctional polymers capable of functioning as field responsive polymers. Our approach utilizes multicomponent polymer systems (block copolymers and graft copolymers), the strategy involves the preparation of block or graft copolymers where the functionalities are limited to different phases in a microphase separated system. Depending on the weight (or volume) fractions of each of the components, different microstructures are possible. And, because of the intimate contact between the functional components, an increase in the synergism between the functionalities may be observed. In this presentation, three examples of multifunctional polymers developed in our labs will be reported. The first class of multifunctional polymers are the microphase separated mixed (ionic and electronic) conducting or MIEC block copolymers. The second class being developed in our labs are the biocompatible conductive materials and the conductive fluids. The final class may be considered microwave active smart polymers.

Syntheses, structures, electrochemistry and catalytic oxidation degradation of organic dyes of two new coordination polymers derived from Cu(II) and Mn(II) and 1-(tetrazo-5-yl)-4-(triazo-1-yl)benzene

NASA Astrophysics Data System (ADS)

Song, Ming; Mu, Bao; Huang, Ru-Dan

2017-02-01

Two new coordination polymers (CPs), namely, [Cu2(ttbz)(H2btc)2(OH)]n (1) and [Mn(ttbz)2(H2O)2]n (2) (Httbz =1-(tetrazo-5-yl)-4-(triazo-1-yl)benzene, H3btc =1,3,5-benzenetricarboxylic acid), have been hydrothermally synthesized and structurally characterized. Complex 1 exhibits a (3,5,5,5)-connected 2D layer with a Schläfli symbol of {3·42}{3·440.520.63}{320.440.520.62}{320.440.530.6}, in which the ttbz- ligand can be described as μ5-bridge, linking Cu(II) ions into a 2D layer and H2btc- ions play a supporting role in complex 1. The ttbz- ligand in complex 2 represents the bridging coordination mode, connecting two Mn(II) ions to form the infinite 1D zigzag chains, respectively, which are further connected by two different types of hydrogen bonds to form a 3D supramolecular. Furthermore, catalytic oxidation activities toward organic dyes and electrochemical behaviors of the title complexes have been investigated at room temperature in aqueous solutions, indicating these complexes may be applicable to color removal in a textile wastewater stream and practical applications in areas of electrocatalytic reduction toward nitrite, respectively.

DFT studies for three Cu(II) coordination polymers: Geometrical and electronic structures, g factors and UV-visible spectra

NASA Astrophysics Data System (ADS)

Ding, Chang-Chun; Wu, Shao-Yi; Xu, Yong-Qiang; Wu, Li-Na; Zhang, Li-Juan

2018-05-01

This work presents a systematic density functional theory (DFT) study for geometrical and electronic structures, g factors and UV-vis spectra of three Cu(II) coordination polymers (CPs) [Cu(XL)(NO3)2]n (1), {[Cu(XL)(4,4‧-bpy)(NO3)2]•CH3CN}n (2) and {[Cu(XL)3](NO3)2·3.5H2O}n (3) based on the ligand N,N‧-bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxdiimide bi(1,2,4-triazole) (XL) with the linker triazole coordinated with copper to construct the CPs. For three CPs with distinct ligands, the optimized molecular structures with PBE0 hybrid functional and the 6-311g basis set agree well with the corresponding XRD data. Meanwhile, the electronic properties are also analyzed for all the systems. The calculated g factors are found sensitive to the (Hartree-Fock) HF character due to the significant hybridization between copper and ligand orbitals. The calculated UV-visible spectra reveal that the main electronic transitions for CP 1 contain d-d and CT transitions, while those for CPs 2 and 3 largely belong to CT ones. The present CPs seem difficult to adsorb small molecules, e.g., CP 1 with H2O and NO2 exhibit unfavorable adsorption and deformation structures near the Cu2+ site.

A three-dimensional coordination polymer based on 1,2,3-triazole-4,5-dicarboxylic acid (H{sub 3}tda): ([Cd{sub 12}(tda){sub 8}(H{sub 2}O){sub 11}] · (H{sub 2}O)6.25){sub n}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Xin-Hui, E-mail: iamxhzhou@njupt.edu.cn; Chen, Qiang

The title coordination polymer ([Cd{sub 12}(tda){sub 8}(H{sub 2}O){sub 11}] · (H{sub 2}O){sub 6.25}){sub n} (H{sub 3}tda = 1,2,3-triazole-4,5-dicarboxylic acid), has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Complex crystallizes in orthorhombic sp. gr. Pmn2{sub 1} with Z = 4. The Cd{sub 2} unit doublebridged by one carboxylate oxygen atom and two neighboring nitrogen atoms from the tda{sup 3–} ligands are linked by the tda{sup 3–}ligands to lead to the 2D (4,4) network in the ac plane. The almost coplanar Cd{sub 2}(μ{sub 5}-tda){sub 2} unit comprised of two Cd ions double-bridged by two tda{sup 3–} ligands through themore » neighboring nitrogen atoms is connected with the other four Cd{sub 2}(μ{sub 5}-tda){sub 2} units form the undulating 2D network in the ac plane. The (4,4) networks and undulating 2D networks are alternatively connected along the b axis by the tda{sup 3–} ligands coordinating to the Cd ions to form the 3D framework.« less

Monomer and metallopolymer compounds of Tb(III) as precursors for OLEDs

NASA Astrophysics Data System (ADS)

Irina, Savchenko; Oleksandra, Berezhnytska; Olena, Trunova; Yaroslav, Fedorov; Sergiy, Smola; Nataliya, Rusakova

2018-03-01

The Terbium (III) complexes [Tb(III)-water, mixed-ligand complex Tb(III)-phenanthroline] with 2-methyl-5-phenyl-1-pentene-3,5-dione were synthesized. The polycomplex was obtained by free-radical polymerization. The results of above studies have shown that the configuration of the chelate unit is unchanged during the polymerization. As a result, the type of coordination was determined and the structure of coordination polyhedra was assumed. The luminescence spectra of obtained metallocomplexes and polymer were investigated and analyzed. The solubilization of terbium complex with phenanthroline, was shown to change luminescence intensity in this complex.