ONE-DIMENSIONAL COORDINATION POLYMERS - APPLICATIONS TO MATERIAL SCIENCE
CT CHEN
1993-01-01
Coordination metal complexes with one-dimensional polymeric structures\\u000a have long been investigated as materials with unusual properties.\\u000a Molecular-based ferromagnets, synthetic metallic conductors, non-linear\\u000a optical materials, and ferroelectrics represent several applications of\\u000a low-dimensional coordination polymers. It is possible to modify the bulk\\u000a magnetic, electrical, and optical properties of such materials by\\u000a tailoring the constituent molecules. This review presents recent\\u000a examples of each
Amo-Ochoa, Pilar; Castillo, Oscar; Gómez-García, Carlos J; Hassanein, Khaled; Verma, Sandeep; Kumar, Jitendra; Zamora, Félix
2013-10-01
Four new copper(II) coordination complexes, obtained by reaction of CuX2 (X = acetate or chloride) with thymine-1-acetic acid and uracil-1-propionic acid as ligands, of formulas [Cu(TAcO)2(H2O)4]·4H2O (1), [Cu(TAcO)2(H2O)2]n (2), [Cu3(TAcO)4(H2O)2(OH)2]n·4H2O (3), and [Cu3(UPrO)2Cl2(OH)2(H2O)2]n (4) (TAcOH = thymine-1-acetic acid, UPrOH = uracil-1-propionic acid) are described. While 1 is a discrete complex, 2-4 are one-dimensional coordination polymers. Complexes 2-4 present dc conductivity values between 10(-6) and 10(-9) S/cm(-1). The magnetic behavior of complex 2 is typical for almost isolated Cu(II) metal centers. Moderate-weak antiferromagnetic interactions have been found in complex 3, whereas a combination of strong and weak antiferromagnetic interactions have been found in complex 4. Quantum computational calculations have been done to estimate the individual "J" magnetic coupling constant for each superexchange pathway in complexes 3 and 4. Compounds 2-4 are the first known examples of semiconductor and magnetic coordination polymers containing nucleobases. PMID:24040754
One-dimensional Coordination Polymer {[Tm2(ttha)(H2O)6Tm2(ttha)(H2O)4]21H2O}n
Gao, Song
-temperature magnetic susceptibility data indicates the presence of an overall antiferromagnetic behaviour with intra- dation of Peking University. Techniques used: FTIR, thermogravimetry, magnetic susceptibility, singleOne-dimensional Coordination Polymer {[Tm2(ttha)(H2O)6Tm2(ttha)(H2O)4]Á21H2O}n: Synthesis, Crystal
Zohreh Rashidi Ranjbar; Ali Morsali; Pascal Retailleau
2011-01-01
The reaction of the zinc(II) acetate and 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene (3-bpdb) in presence of perchlorate anions produces a new one-dimensional coordination polymer, {[Zn(?-3-bpdb)(3-bpdb)2(H2O)2](ClO4)2·3-bpdb}n (1). The compound 1 has been characterized by IR, 1HNMR and 13CNMR spectroscopies. The single crystal X-ray data shows an infinite one-dimensional structure that grows in two- and three-dimensions by hydrogen bonding and ?–? stacking. The compound 1 also
Croitor, Lilia; Coropceanu, Eduard B; Petuhov, Oleg; Krämer, Karl W; Baca, Svetlana G; Liu, Shi-Xia; Decurtins, Silvio; Fonari, Marina S
2015-05-01
A one-dimensional linear coordination polymer {[Cu3(?3-OH)(2-pyao)3(bdc)]·6(H2O)}n () composed of trinuclear [Cu3(?3-OH)(2-pyao)3](2+) metallacrown cores bridged by bis-carboxylato linkers has been obtained by treatment of copper(ii) fluoride with pyridine-2-aldoxime (2-pyaoH) ligand and benzene-1,4-dicarboxylic acid (H2bdc). Magnetic susceptibility measurements show strong antiferromagnetic interactions between Cu(ii) centers within the trinuclear metallacrown core with J = -430 cm(-1). PMID:25823875
Braverman, Maxwell A; Nettleman, Joseph H; Supkowski, Ronald M; LaDuca, Robert L
2009-06-01
Copper phthalate coordination polymers incorporating the kinked and hydrogen-bonding-capable imines 4,4'-dipyridylketone (dpk) and 4,4'-dipyridylamine (dpa) have been prepared and structurally characterized by single-crystal X-ray diffraction. {[Cu(pht)(dpk)].0.33CH(3)OH}(n) (1; pht = phthalate) possesses helical subunits built from the fusion of [Cu(dpk)](n) 3-fold double helices and [Cu(pht)](n) 3-fold helices with opposite handedness. The resulting achiral [Cu(pht)(dpk)](n) helices are conjoined by bridging phthalate carboxylate oxygen atoms to construct {Cu(2)O(2)} dimeric units, which serve as 8-connected nodes for a three-dimensional (3D) coordination polymer lattice with an unprecedented 3(6)4(12)5(8)6(2) topology, evocative of a 3D Kagome lattice. {[Cu(2)(pht)(2)(dpa)].H(2)O}(n) (2) manifests homochiral septuple left-handed [Cu(2)O(2)(dpa)](n) helices formed by copper ions, phthalate oxygen atoms, and dpa ligands. The septuple helices are bracketed by pht anions to construct chiral one-dimensional nanobarrels with solvent-free "star-shaped" channels. Compounds 1 and 2 display antiferromagnetic [J = -9.85(5) cm(-1)] and ferromagnetic [J = +1.36(3) cm(-1)] coupling across their {Cu(2)O(2)} dimeric units, respectively. PMID:19382760
One-dimensional transport in polymer nanofibers
A. N. Aleshin; H. J. Lee; Y. W. Park; K. Akagi
2004-10-08
We report our transport studies in quasi one-dimensional (1D) conductors - helical polyacetylene fibers doped with iodine and the data analysis for other polymer single fibers and tubes. We found that at 30 K < T < 300 K the conductance and the current-voltage characteristics follow the power law: G(T) ~ T^alpha with alpha ~ 2.2-7.2 and I(V) ~ V^betta with betta ~ 2-5.7. Both G(T) and I(V) show the features characteristic of 1D systems such as Luttinger liquid or Wigner crystal. The relationship between our results and theories for tunneling in 1D systems is discussed.
Asymmetrically doped one-dimensional trans-polymers
NASA Astrophysics Data System (ADS)
Caldas, Heron
2009-10-01
More than 30 years ago [H. Shirakawa, E.J. Louis, A.G. MacDiarmid, C.K. Chiang, A.J. Heeger, J. Chem. Soc. Chem. Comm. 578 (1977); S. Etemad, A.J. Heeger, Ann. Rev. Phys. Chem. 33 (1982) 443] it was discovered that doped trans-polyacetylene (CH)x, a one-dimensional (1D) conjugated polymer, exhibits electrical conductivity. In this work we show that an asymmetrically doped 1D trans-polymer has non-conventional properties, as compared to symmetrically doped systems. Depending on the level of asymmetry between the chemical potentials of the two involved fermionic species, the polymer can be in a partially or fully spin polarized state. Some possible experimental consequences of doped 1D trans-polymers used as 1D organic polarized conductors are discussed.
NASA Astrophysics Data System (ADS)
Sarkar, Bhola Nath; Bhar, Kishalay; Chattopadhyay, Soumi; Das, Sumitra; Mitra, Partha; Ghosh, Barindra Kumar
2010-01-01
Two heptacoordinated one-dimensional coordination polymers of the type [Cd(L)(dca)] n(X) n ( 1 and 2) [L = N, N'-(bis-(pyridin-2-yl)benzylidene)diethylenetriamine; dca = dicyanamide; X = ClO4- ( 1), PF6- ( 2)] have been prepared and characterized on the basis of microanalytical, spectroscopic and other physicochemical properties. Structures of 1 and 2 are solved by single crystal X-ray diffraction measurements. Structural study reveals that in both compounds each cadmium(II) center adopts a distorted pentagonal bipyramidal geometry with a CdN 7 chromophore coordinated by five N atoms of the pentadentate Schiff base and two nitrile N atoms of single bridged dca in ? 1,5 fashion. The polynuclear units in 1 are engaged in weak N-H…O and C-H…O hydrogen bondings with perchlorate ions embedded among the chains to give a 2D sheet structure. In the long-range form, the 1D polymeric chains of 2 pack through N-H…F and C-H…F hydrogen bonds with hexafluorophosphate placed in between chains resulting a 2D continuum. The complexes display intraligand 1(?-??) fluorescence in DMF solutions at room temperature.
NASA Astrophysics Data System (ADS)
Kundu, Subhasish; Roy, Subhasis; Bhar, Kishalay; Ghosh, Rajarshi; Lin, Chia-Her; Ribas, Joan; Ghosh, Barindra Kumar
2013-04-01
Two neutral one-dimensional coordination polymers of the type [M(L)(?1,5-dca)(dca)]n [M = Co (1), Ni (2); L = (N,N-diethyl,N'-(pyridin-2-yl)benzylidene)ethane-1,2-diamine; dca = dicyanamide] are isolated through single-pot reactions of a 1:1:2 M ratio of M(OAc)2·4H2O, L and Na(dca) in MeOH solution at room temperature and characterized on the basis of microanalyses, spectroscopic, thermal and other physicochemical results. X-ray structural study reveals that each metal(II) center in both compounds adopts a distorted octahedral geometry with an MN6 chromophore coordinated by three N atoms of the tridentate Schiff base (L) and three nitrile N atoms of one terminal and two single ?1,5 bridged dca units in a meridional alignment; each ?1,5 bridged dca unit connects other neighboring metal centers in a non-ending fashion affording a 1D chain. Variable-temperature magnetic susceptibility measurements of 1 and 2 show weak antiferromagnetic interactions among the metal centers through ?1,5 dca bridges.
One-dimensional exciton diffusion in a conjugated polymer
NASA Astrophysics Data System (ADS)
Rughooputh, S. D. D. V.; Bloor, D.; Phillips, D.; Movaghar, B.
1987-05-01
One of the most interesting questions in modern transport theory has been and still is the following: What is the influence of dimensionality (including fractal) on the carrier and exciton dynamics and decay kinetics in quasiordered and disordered systems. An enormous amount of theoretical work has been done in this field, extended now to include direct computer simulations. Experimental data have been more difficult to find and are consequently sparse and not always convincing. Certain types of organic compounds and, in particular polydiacetylenes, constitute unique classes of nearly one-dimensional systems. Studies including photoconductive decays have been extended to include picosecond luminescence decay on PDA-1OH [poly(diacetylene-1-hydroxy-hexadyine-diol)], a continuous highly oriented fibrous polymer. The decay laws are compared with exact results in dimensionalities d=1 and near 1. The present data together with the recent work on doped tetramethylammonium manganese trichloride may be evidence for the first time of one-dimensional exciton motion.
Arpi Majumder; Matthias Westerhausen; Alexander N. Kneifel; Jean-Pascal Sutter; Nathalie Daro; Samiran Mitra
2006-01-01
One-dimensional organic\\/inorganic composite coordination polymer has been synthesised by the reaction of manganese(II) chloride with the chelating bidentate ligand, 1,10-phenanthroline (1,10-phen). X-ray single crystal analysis shows a doubly chloride bridged 1-D polymer, [Mn(?-Cl)2(phen)]n (1), where manganese(II) ions possess octahedral environment. The complex is characterised by elemental analysis, different spectroscopic, electrochemical and low temperature magnetic susceptibility measurements. 1 exhibits strong fluorescence
Calculations on the One-dimensional H-Atom in Coordinate and Momentum Space
Rioux, Frank
Calculations on the One-dimensional H-Atom in Coordinate and Momentum Space Frank Rioux Chemistry-dimensional hydrogen atom. 1s 1 x( ) 2 x exp x-( ):= 2s 2 x( ) 1 8 x 2 x-( ) exp x 2 - := 3s 3 x( ) 2 243 3 x 27: x 2 x exp x-( )( ) d d 0= solve x, 1 Calculate the average value of the electron position: 0 x1 x
Improving brush polymer infrared one-dimensional photonic crystals via linear polymer additives.
Macfarlane, Robert J; Kim, Bongkeun; Lee, Byeongdu; Weitekamp, Raymond A; Bates, Christopher M; Lee, Siu Fung; Chang, Alice B; Delaney, Kris T; Fredrickson, Glenn H; Atwater, Harry A; Grubbs, Robert H
2014-12-17
Brush block copolymers (BBCPs) enable the rapid fabrication of self-assembled one-dimensional photonic crystals with photonic band gaps that are tunable in the UV-vis-IR, where the peak wavelength of reflection scales with the molecular weight of the BBCPs. Due to the difficulty in synthesizing very large BBCPs, the fidelity of the assembled lamellar nanostructures drastically erodes as the domains become large enough to reflect IR light, severely limiting their performance as optical filters. To overcome this challenge, short linear homopolymers are used to swell the arrays to ?180% of the initial domain spacing, allowing for photonic band gaps up to ?1410 nm without significant opacity in the visible, demonstrating improved ordering of the arrays. Additionally, blending BBCPs with random copolymers enables functional groups to be incorporated into the BBCP array without attaching them directly to the BBCPs. The addition of short linear polymers to the BBCP arrays thus offers a facile means of improving the self-assembly and optical properties of these materials, as well as adding a route to achieving films with greater functionality and tailorability, without the need to develop or optimize the processing conditions for each new brush polymer synthesized. PMID:25373000
Polymer-loaded propagating modes on a one-dimensional photonic crystal
Han, Lu; Zhang, Douguo, E-mail: dgzhang@ustc.edu.cn; Chen, Yikai; Wang, Ruxue; Zhu, Liangfu; Wang, Pei; Ming, Hai; Lakowicz, Joseph R., E-mail: jlakowicz@som.umaryland.edu [Department of Optics and Optical Engineering, Institute of Photonics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Badugu, Ramachandram [Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland 21201 (United States)
2014-02-10
We numerically and experimentally demonstrate that a polymer film-coated one-dimensional photonic crystal (1DPC) can sustain transverse electric (TE) polarized modes without the limit of guided layer's thickness. Our results indicate that two propagating modes are existing inside the polymer film, the first one is the TE polarized Bloch surface wave, and the second one is the TE polarized guided mode. Here in, the evolution of these two modes with change in the polymer film thickness is presented. Our numerical simulation results are in well-agreement with the experimental data obtained using back focal plane imaging.
Universal reduction of effective coordination number in the quasi-one-dimensional Ising model
NASA Astrophysics Data System (ADS)
Todo, Synge
2006-09-01
Critical temperature of quasi-one-dimensional general-spin Ising ferromagnets is investigated by means of the cluster Monte Carlo method performed on infinite-length strips, L×? or L×L×? . We find that in the weak interchain coupling regime the critical temperature as a function of the interchain coupling is well-described by a chain mean-field formula with a reduced effective coordination number, as the quantum Heisenberg antiferromagnets recently reported by Yasuda [Phys. Rev. Lett. 94, 217201 (2005)]. It is also confirmed that the effective coordination number is independent of the spin size. We show that in the weak interchain coupling limit the effective coordination number is, irrespective of the spin size, rigorously given by the quantum critical point of a spin- 1/2 transverse-field Ising model.
Cellular reprogramming dynamics follow a simple one-dimensional reaction coordinate
Pusuluri, Sai Teja; Mehta, Pankaj; Castillo, Horacio E
2015-01-01
Cellular reprogramming, the conversion of one cell type to another, has fundamentally transformed our conception of cell types. Cellular reprogramming induces global changes in gene expression involving hundreds of transcription factors and thousands of genes and understanding how cells globally alter their gene expression profile during reprogramming is an open problem. Here we reanalyze time-series data on cellular reprogramming from differentiated cell types to induced pluripotent stem cells (iPSCs) and show that gene expression dynamics during reprogramming follow a simple one-dimensional reaction coordinate. This reaction coordinate is independent of both the time it takes to reach the iPSC state as well as the details of experimental protocol used. Using Monte-Carlo simulations, we show that such a reaction coordinate emerges naturally from epigenetic landscape models of cell identity where cellular reprogramming is viewed as a "barrier-crossing" between the starting and ending cell fates. The model als...
Moon, Bokhee; Jeon, Youngeun; Moon, Suk-Hee; Park, Ki-Min
2014-01-01
The asymmetric unit of the title compound, {[Ag(C11H11N3)]NO3·2(CH3)2SO}n, comprises one AgI atom, one N-(pyridine-4-ylmethyl)pyridine-3-amine ligand, one nitrate anion and two dimethyl sulfoxide molecules. The AgI atoms are bridged by two pyridine N atoms from two symmetry-related ligands, forming a helical chain and adopting a slightly distorted linear coordination geometry [N—Ag—N = 175.37?(8)°]. The helical chain, with a pitch length of 16.7871?(8)?Å, propagates along the b-axis direction. In the crystal, symmetry-related right- and left-handed helical chains are alternately arranged via Ag?Ag interactions [3.4145?(4)?Å] and ?–? stacking interactions [centroid–centroid distance = 3.650?(2)?Å], resulting in the formation of a two-dimensional supramolecular network extending parallel to (100). Weak Ag?O [2.775?(2), 3.169?(4) and 2.690?(2)?Å] interactions, as well as several N—H?O and C—H?O hydrogen-bonding interactions, contribute to the stabilization of the crystal structure. Parts of the dimethyl sulfoxide solvent molecule are disordered over two sets of sites in a 0.937?(3):0.063?(3) ratio. PMID:25552978
NASA Astrophysics Data System (ADS)
Guduru, Surya S. K.; Scotognella, Francesco; Criante, Luigino; Vazquez, Rebeca Martinez; Ramponi, Roberta; Vishnubhatla, Krishna Chaitanya
2014-07-01
We report the fabrication of micro-Fresnel lenses by femtosecond laser surface ablation on one-dimensional (1-D) polymer photonic crystals. This device is designed to focus the transmitted wavelength (520 nm) of the photonic crystal and filter the wavelengths corresponding to the photonic band-gap region (centered at 630 nm, ranging from 530 to 700 nm). Integration of such devices in a wavelength selective light harvesting and filtering microchip is envisaged.
Specific heat study of quasi-one-dimensional antiferromagnetic model for an organic polymer chain
NASA Astrophysics Data System (ADS)
Qu, Shao-Hua; Zhu, Lin
2008-09-01
The specific heat of an infinite one-dimensional polymer chain bearing periodically arranged side radicals connected to the even sites is studied by means of quantum transfer-matrix method based on a Ising-Heisenberg model. In the absence of the exchange interactions between side radicals and the main chain, the curves of specific heat show a round peak due to the antiferromagnetic excitations for the all antiferromagnetic interactions along the polymer chain. Considering the exchange interactions between the side radicals and the main chain, the curves of the specific heat show double-peak structure for ferromagnetic interactions between the radicals and main chain, indicating that a competition between ferromagnetic and antiferromagnetic interactions and the possibility of the occurrence of the stable ferrimagnetic state along the polymer chain.
Fornasari, L.; Floris, F.; Patrini, M.; Guizzetti, G.; Marabelli, F., E-mail: franco.marabelli@unipv.it [Dipartimento di Fisica, Università degli Studi di Pavia, via Bassi 6, 27100 Pavia (Italy); Canazza, G.; Comoretto, D. [Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, via Dodecaneso 31, 16146 Genova (Italy)
2014-08-04
We demonstrate photoluminescence excitation enhancement in an all-polymer flexible one-dimensional photonic crystal structure capped with a fluorescent organic ultrathin film. When optical matching conditions between the excitation beam and the Bloch Surface Wave mode supported by the photonic structure are achieved, a ten times enhancement of the photoluminescence is observed. We notice that in these systems luminescence signal reinforcement is achieved by increasing the pump efficiency with no need of spectral resonance to the emission of the chosen fluorophore. All these features make these systems suitable candidates for easy, flexible, and cheap fluorescent sensing.
Campbell, D.K.; Baeriswyl, D.; Mazumdar, S.
1986-01-01
We review recent results on the role of electron-electron (e-e) interactions in quasi-one-dimensional conducting polymers and related systems. Within the Peierls-Hubbard model, the effects of both short-range (on-site U and nearest neighbor V/sub 1/) and long-range (V/sub j/, jgreater than or equal to 2) are examined, the former using quantum Monte Carlo and the latter with exact diagonalization of finite size systems and analytic arguments. We also discuss optical absorption properties in the presence of electronic correlation, focusing on the weak and strong coupling limits.
Pseudo one-dimensional analysis of polymer electrolyte fuel cell cold-start
Mukherjee, Partha P [Los Alamos National Laboratory; Mukundan, Rangachary [Los Alamos National Laboratory; Borup, Rodney L [Los Alamos National Laboratory; Wang, Yun [NON LANL; Mishlera, Jeff [NON LANL
2009-01-01
This paper investigates the electrochemical kinetics, oxygen transport, and solid water formation in polymer electrolyte fuel cell (PEFC) during cold start. Following [Yo Wang, J. Electrochem. Soc., 154 (2007) B1041-B1048], we develop a pseudo one-dimensional analysis, which enables the evaluation of the impact of ice volume fraction and temperature variations on cell performance during cold-start. The oxygen profile, starvation ice volume fraction, and relevant overpotentials are obtained. This study is valuable for studying the characteristics of PEFC cold-start.
Coulomb-blockade transport in quasi-one dimensional polymer nanofibers
A. N. Aleshin; H. J. Lee; S. H. Jhang; H. S. Kim; K. Akagi; Y. W. Park
2005-07-22
We report the low temperature current-voltage (I-V) characteristics studies in quasi-one dimensional conducting polymer nanofibers. We find a threshold voltage Vt below which little current flows at temperatures below 30-40 K. For V > Vt current scales as (V/Vt - 1)^zeta, where zeta ~ 1.8-2.1 at high biases. Differential conductance oscillations are found whose magnitude increases as temperature decreases below 10 K. We attribute the observed low temperature I-V behavior to Coulomb blockade effects with a crossover to Luttinger liquid-like behavior at high temperature. We demonstrate that at low temperatures such a doped conjugated polymer fiber can be considered as an array of small conducting regions separated by nanoscale barriers, where the Coulomb blockade tunneling is the dominant transport mechanism.
Solitons and polarons in quasi-one dimensional conducting polymers and related materials
Campbell, D.K.
1983-01-01
In recent years it has become increasingly appreciated that fundamentally nonlinear excitations - solitons - play an essential role in an incredible variety of natural systems. These solitons, which frequently exhibit remarkable stability under interactions and perturbations, often dominate the transport, response, or structural properties of the systems in which they occur. In this article, we present an introduction to the solitons that occur in quasi-one-dimensional conducting polymers (synmetals) and related systems. The relevance of this subject to molecular electronic devices is twofold. First, many of these materials have molecular structures similar to possible prototype molecular switches. Second, to understand in detail how a molecular electronic device could work, it is essential to have a broad perspective on the nature of possible excitations in a variety of natural and synthetic molecular materials. 51 references.
Kim, Phil Yong; Oh, Jeong-Wook; Nam, Jwa-Min
2015-07-01
We report a robust one-dimensional (1D) nanoparticle-assembly strategy that uses the self-assembly of nanoparticles with ligand and thermal controls, polyethylene glycol (PEG) with thiol and carboxyl groups, and nanoparticle oligomer and polymer codewetting process to form ultralong and continuous 1D nanochains. The 1D nanochains were assembled with closely packed 1D nanoparticle oligomer building blocks, elongated and buttressed by dynamic 1D PEG templates formed on a hydrophobic surface via anisotropic spinodal dewetting. Using this strategy, nanoparticle-packed 1D nanochains (?1 nm interparticle spacing) were fabricated with ?60 nm-width and a few to >10 ?m-length (nearly 20 ?m in some cases) from 20 nm gold nanoparticles. Our findings offer insights and open revenues for particle assembly processes and, as given by 'universality in colloid aggregation', should be readily applicable to various nanoparticles. PMID:26067225
NASA Astrophysics Data System (ADS)
Zhao, Guo-Zhong; Yu, Xi-Jun; Guo, Peng-Yun
2013-05-01
In this paper, a Petrov—Galerkin scheme named the Runge—Kutta control volume (RKCV) discontinuous finite element method is constructed to solve the one-dimensional compressible Euler equations in the Lagrangian coordinate. Its advantages include preservation of the local conservation and a high resolution. Compared with the Runge—Kutta discontinuous Galerkin (RKDG) method, the RKCV method is easier to implement. Moreover, the advantages of the RKCV and the Lagrangian methods are combined in the new method. Several numerical examples are given to illustrate the accuracy and the reliability of the algorithm.
Communications Two Luminescent Coordination Polymers
zur Loye, Hans-Conrad
is to incorporate them into a polymeric structure, such as an all-organic polymer,6 or into a mixed inorganic incorporation into inorganic/organic coordination polymers can offer the advantages of higher thermal stability polymers could significantly impact the field of electroluminescent devices in the future10 as one can
Controlled assembly of graphene oxide nanosheets within one-dimensional polymer nanostructure.
Park, Ho Seok; Choi, Bong Gill; Hong, Won Hi; Jang, Sung-Yeon
2013-09-15
We have demonstrated that the location and distribution of graphene oxide nanosheets (GONs) confined in 1D polymer composites were readily controlled depending on the processing conditions of electrospinning such as the types of polymers and the solvents used for the fabrication. The uniform bead-free poly(vinyl alcohol) (PVA)/GON composite nanofibers (NFs) even at high GON loading were obtained from the homogeneous polymer solutions attributable to the favorable interactions, as elucidated by spectroscopic data, thereby showing significant enhancement of their physical properties. The GONs were localized in the surface regions of the PVA-NFs due to the rapid convective evaporation of the water molecules, with concomitant aggregation into several sheets (<10 layers). In contrast, the co-continuous internal morphology of PVA/GON-NFs was constructed using less-volatile, polar dimethylformamide (DMF) solvents. Furthermore, the GONs were uniformly distributed in the more compatible polymer matrices such as polyacrylonitrile (PAN) and polystyrene (PS). Therefore, the distribution of GONs in 1D nanofibers was governed by the kinetics of solvent evaporation and the interaction with the polymer matrices. PMID:23810546
Transition state theory approach to polymer escape from a one dimensional potential well
NASA Astrophysics Data System (ADS)
Mökkönen, Harri; Ikonen, Timo; Ala-Nissila, Tapio; Jónsson, Hannes
2015-06-01
The rate of escape of an ideal bead-spring polymer in a symmetric double-well potential is calculated using transition state theory (TST) and the results compared with direct dynamical simulations. The minimum energy path of the transitions becomes flat and the dynamics diffusive for long polymers making the Kramers-Langer estimate poor. However, TST with dynamical corrections based on short time trajectories started at the transition state gives rate constant estimates that agree within a factor of two with the molecular dynamics simulations over a wide range of bead coupling constants and polymer lengths. The computational effort required by the TST approach does not depend on the escape rate and is much smaller than that required by molecular dynamics simulations.
Gao, Song
and nonlinear ac susceptibility measurements, demonstrate that the long-range magnetic ordering and spin glass Cyano-Bridged Polymers Dongfeng Li,*, Limin Zheng, Yuanzhu Zhang, Jin Huang, Song Gao,*, and Wenxia Tang,2-bipyridines coordinated to the metal ions Co2+ for 1 and Mn2+ for 2. Magnetic studies, including linear
Nanojunction between fullerene and one-dimensional conductive polymer on solid surfaces.
Nakaya, Masato; Okawa, Yuji; Joachim, Christian; Aono, Masakazu; Nakayama, Tomonobu
2014-12-23
Bottom-up creation of huge molecular complexes by covalently interconnecting functional molecules and conductive polymers is a key technology for constructing nanoscale electronic circuits. In this study, we have created an array of molecule-polymer nanojunctions from C60 molecules and polydiacetylene (PDA) nanowires at designated positions on solid surfaces by controlling self-assemblies and intermolecular chemical reactions of molecular ingredients predeposited onto the surfaces. In the proposed method, the construction of each nanojunction spontaneously proceeds via two types of chemical reactions: a chain polymerization among self-assembled diacetylene compound molecules for creating a single PDA nanowire and a subsequent cycloaddition reaction between the propagating forefront part of the PDA backbone and a single C60 molecule adsorbed on the surface. Scanning tunneling microscopy has proved that the C60 molecule is covalently connected to each end of the ?-conjugated PDA backbone. Furthermore, the decrease in the energy gap of the C60 molecule in nanojunctions is observed as compared with that of pristine C60 molecules, which is considered to be due to the covalent interaction between the PDA edge and the C60 molecule. PMID:25469761
A novel one-dimensional Ni(II)Fe(II) polymer containing l3-cyanides: [Ni(cyclen)]2[Fe(CN)6]8H2O
Gao, Song
The temperature dependence of the magnetic susceptibility wM of 1 was investigated from 2 to 300 K (Fig. 3A novel one-dimensional Ni(II)Fe(II) polymer containing l3-cyanides: [Ni(cyclen)]2[Fe(CN)6]Á8H2O-N3)2(232-tet)2](PF6)2 . Moderate antiferro- magnetic coupling occurs between the Ni2+ ions
Tsai, Hui-Lien; Yang, Chen-I; Wernsdorfer, Wolfgang; Huang, Siang-Hua; Jhan, Siang-Yu; Liu, Ming-Hsuan; Lee, Gene-Hsiang
2012-12-17
Two Mn(4) single-molecule-magnet (SMM)-based coordination polymers, {[Mn(4)O(salox)(3)(N(3))(3)(DMF)(2)(H(2)O)(dpp)]·0.5MeOH}(n) (1·0.5MeOH; H(2)salox = salicylaldoxime; dpp = 1,3-di-4-pyridylpropane; DMF = N,N-dimethylformamide) and {[Mn(4)O(Me-salox)(3)(N(3))(3)(dpp)(1.5)]·1.5Et(2)O}(n) (2·1.5Et(2)O; Me-H(2)salox = hydroxyphenylethanone oxime), are self-assembled from Mn(ClO(4))(2)·6H(2)O/H(2)salox and Mn(ClO(4))(2)·6H(2)O/Me-H(2)salox systems with dpp and NaN(3) in DMF/MeOH, respectively. Both compounds comprise a mixed-valence tetranuclear manganese core, [Mn(II)Mn(III)(3)O](9+), which serves as a building unit for subsequent assembly via oximate and azido ligands. The flexible dpp ligand links with a Mn(4) unit, leading to the formation of a one-dimensional helical structure in 1·0.5MeOH and a three-dimensional pcu network in 2·1.5Et(2)O. The magnetic data analysis shows that antiferromagnetic interactions within the Mn(4) units resulted in S = (3)/(2) and (7)/(2) ground states for 1·0.5MeOH and 2·1.5Et(2)O, respectively. Both compounds show SMM behavior, as evidenced by frequency-dependent out-of-phase signals in alternating-current magnetic susceptibility and magnetic hysteresis loop studies with an energy barrier of U(eff) = 37 K for 2·1.5Et(2)O. PMID:23215243
Sakiyama, Yukinori; Graves, David B. [Department of Mechanical Engineering, University of Tokyo, Tokyo 113-8656 (Japan); Department of Chemical Engineering, University of California, Berkeley, California 94720 (United States)
2007-04-01
We present one-dimensional simulations of atmospheric pressure rf-excited plasma with two concentric spherical electrodes and the inner electrode powered. The gas used is helium with 0.1% nitrogen addition. The gap distance between the inner and outer electrodes is 1 mm. The coupled continuity equations and electron energy equation are solved with Poisson's equation using the finite element method. A mode transition is observed in the discharge power-voltage curve between 1 and 1000 mW. In the low power mode, ionization rate peaks only near the inner electrode. The electron-impact excitation and ionization rates peak in the local cathodic phase. In the high power mode, the rate of ionization peaks near the outer electrode as well as the inner electrode. The inner sheath significantly shrinks and the direct electron-impact ionization is the primary ionization reaction near the inner electrode. The ionization rate near the outer electrode is due to Ohmic sheath oscillation heating of electrons, resulting in a peak in metastable helium creation. Penning ionization is the major ionization reaction near the outer electrode. Thus, two different ionization mechanisms coexist near the inner and outer electrodes. Electron heating near the outer electrode may have implications for surface processing in atmospheric pressure microdischarges. The local field approximation (LFA) in high power mode fails to predict the ionization rate peak near the outer electrode due to its inability to properly account for electron diffusion in the presence of both a strong electric field and electron density gradient. However, use of the LFA is adequate to model the low power mode and it correctly predicts the existence of the mode transition.
NASA Astrophysics Data System (ADS)
Sakiyama, Yukinori; Graves, David B.
2007-04-01
We present one-dimensional simulations of atmospheric pressure rf-excited plasma with two concentric spherical electrodes and the inner electrode powered. The gas used is helium with 0.1% nitrogen addition. The gap distance between the inner and outer electrodes is 1mm. The coupled continuity equations and electron energy equation are solved with Poisson's equation using the finite element method. A mode transition is observed in the discharge power-voltage curve between 1 and 1000mW. In the low power mode, ionization rate peaks only near the inner electrode. The electron-impact excitation and ionization rates peak in the local cathodic phase. In the high power mode, the rate of ionization peaks near the outer electrode as well as the inner electrode. The inner sheath significantly shrinks and the direct electron-impact ionization is the primary ionization reaction near the inner electrode. The ionization rate near the outer electrode is due to Ohmic sheath oscillation heating of electrons, resulting in a peak in metastable helium creation. Penning ionization is the major ionization reaction near the outer electrode. Thus, two different ionization mechanisms coexist near the inner and outer electrodes. Electron heating near the outer electrode may have implications for surface processing in atmospheric pressure microdischarges. The local field approximation (LFA) in high power mode fails to predict the ionization rate peak near the outer electrode due to its inability to properly account for electron diffusion in the presence of both a strong electric field and electron density gradient. However, use of the LFA is adequate to model the low power mode and it correctly predicts the existence of the mode transition.
Synthesis ZnO nanoparticles from a new Zinc(II) coordination polymer precursor
Fahime Bigdeli; Ali Morsali
2010-01-01
A new zinc(II) nitrite coordination polymer, [Zn(3-bpdh)(NO2)2]n (1), 3-bpdh=2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene} was prepared and characterized by elemental analyses and IR spectroscopy. Compound 1 was structurally characterized by single-crystal X-ray diffraction and is one-dimensional polymer with coordination environment of distorted octahedral, ZnN2O4. Thermal decomposition of this precursor in oleic acid at 240°C under air atmosphere results in the formation of nanoparticles of ZnO.
Supramolecular coordination polymers in water: rings, chains and networks
T. Vermonden
2005-01-01
Supramolecular polymers are polymers in which the monomers are held together by non-covalent interactions. In solution these polymers can break and recombine reversibly yielding polymers with an average degree of polymerization. This thesis is devoted to water-soluble coordination polymers, in which the bonds between the monomers are based on metal ion coordination. The most successful ligands used in this research
Li, Liangchun; Matsuda, Ryotaro; Tanaka, Iku; Sato, Hiroshi; Kanoo, Prakash; Jeon, Hyung Joon; Foo, Maw Lin; Wakamiya, Atsushi; Murata, Yasujiro; Kitagawa, Susumu
2014-05-28
A porous coordination polymer (PCP) has been synthesized employing an organic ligand in which a stable free radical, isoindoline nitroxide, is incorporated. The crystalline PCP possesses one-dimensional channels decorated with the nitroxyl catalytic sites. When O2 gas or air was used as the oxidant, this PCP was verified to be an efficient, recyclable, and widely applicable catalyst for selective oxidation of various alcohols to the corresponding aldehydes or ketones. PMID:24816302
Crystal structures of coordination polymers from CaI2 and proline
Lamberts, Kevin; Englert, Ulli
2015-01-01
Completing our reports concerning the reaction products from calcium halides and the amino acid proline, two different solids were found for the reaction of l- and dl-proline with CaI2. The enantiopure amino acid yields the one-dimensional coordination polymer catena-poly[[aqua-?3-l-proline-tetra-?2-l-proline-dicalcium] tetraiodide 1.7-hydrate], {[Ca2(C5H9NO2)5(H2O)]I4·1.7H2O}n, (1), with two independent Ca2+ cations in characteristic seven- and eightfold coordination. Five symmetry-independent zwitterionic l-proline molecules bridge the metal sites into a cationic polymer. Racemic proline forms with Ca2+ cations heterochiral chains of the one-dimensional polymer catena-poly[[diaquadi-?2-dl-proline-calcium] diiodide], {[Ca(C5H9NO2)2(H2O)2]I2}n, (2). The centrosymmetric structure is built by one Ca2+ cation that is bridged towards its symmetry equivalents by two zwitterionic proline molecules. In both structures, the iodide ions remain non-coordinating and hydrogen bonds are formed between these counter-anions, the amino groups, coordinating and co-crystallized water molecules. While the overall composition of (1) and (2) is in line with other structures from calcium halides and amino acids, the diversity of the carboxylate coordination geometry is quite surprising.
Gao, Song
Two-dimensional rare earth coordination polymers involving different coordination modes Key Laboratory of Rare Earth Materials Chemistry and Applications, PKU-HKU Joint Laboratory on Rare; Coordination modes; Double-layered structure; Lanthanide 1. Introduction Coordination polymers of rare earth
Shyamapada Shit; Joy Chakraborty; Anamika Das; Glenn P. A. Yap; M. S. El. Fallah; Samiran Mitra
2007-01-01
A one-dimensional (1-D) copper(II) coordination polymer [Cu(maleate)(2,2?-bipyridyl)]\\u000a n\\u000a ?2H2O has been synthesised. Single crystal X-ray diffraction study reveals that maleate ion bridges two adjacent copper(II) centres\\u000a along the chain in a syn–anti fashion. A complete cryomagnetic investigation of the title complex correlates well with the distorted square pyramidal geometry\\u000a of the central copper(II) ion and bridging nature of the maleate.
Syntheses, structural analyses and luminescent property of four alkaline-earth coordination polymers
Zhang, Sheng; Qu, Xiao-Ni; Xie, Gang; Wei, Qing; Chen, San-Ping, E-mail: sanpingchen@126.com
2014-02-15
Four alkaline-earth coordination polymers, [Ba(Pzdc)(H{sub 2}O)]{sub n} (1), [Ba(Pzdc)]{sub n} (2), [AgSr(Pzdc)(NO{sub 3})(H{sub 2}O)]{sub n} (3), [Ag{sub 2}Ca(Pzdc){sub 2}(H{sub 2}O)]{sub n} (4) (H{sub 2}Pzdc=2, 3-pyrazinedicarboxylic acid) have been synthesized and characterized by single-crystal X-ray diffraction. Compounds 1 and 2 afford 2D layer networks generated by one-dimensional chains containing the [Ba{sub 2}O{sub 11}N] units. Compound 3 is of 2D mixed-metal coordination network formed by one-dimensional chain units, while 4 is of a 3D heterometallic framework. Interestingly, 1 and 2 can undergo reversible SCSC structural transformation upon dehydration/rehydration of coordinated water molecules. In addition, the ?–? stacking interactions dominate fluorescent properties of compounds 1 and 2. - Graphical abstract: Four new coordination polymers [Ba(Pzdc)(H{sub 2}O)]{sub n} (1), [Ba(Pzdc)]{sub n} (2), [AgSr(Pzdc)(NO{sub 3})(H{sub 2}O)]{sub n} (3), [Ag{sub 2}Ca(Pzdc){sub 2}(H{sub 2}O)]{sub n} (4) (H{sub 2}Pzdc=2, 3-pyrazinedicarboxylic acid) have been synthesized. Compounds 1–3 display 2D topology structures and compound 4 exhibits a 3D topology structure. Fortunately, 1 and 2 undergo reversible dehydration/rehydration of coordinated water molecules. Display Omitted - Highlights: • All structures are generated by 1D chains. • 1 and 2 show reversible dehydration/rehydration of coordinated water molecules. • The ?–? stacking interactions dominate fluorescent properties of compounds 1 and 2.
The One-Dimensional Random Walk
NSDL National Science Digital Library
McGath, Gary
Created by authors Gary McGath and Paul Trunfio of Boston University's Center for Polymer Studies, this is the description and instructions for the One-Dimensional Random Walk applet. This Applet relates random coin-flipping to random motion. It strives to show that randomness (coin-flipping) leads to some sort of predictable outcome (the bell-shaped curve).
Coordination polymers of uranium(IV) terephthalates.
Falaise, Clément; Assen, Ayalew; Mihalcea, Ionut; Volkringer, Christophe; Mesbah, Adel; Dacheux, Nicolas; Loiseau, Thierry
2015-02-14
A series of tetravalent uranium terephthalates has been solvothermally synthesized in the solvent N,N-dimethylformamide (DMF) at temperature 100-150 °C with different water amounts. Composition diagrams have been determined for the U(4+) metallic cation in the presence of terephthalic acid, and their crystal structures revealed the occurrence of two- or three-dimensional coordination polymers. In the absence of water, a mixture of two polytypes T-U(2)Cl(2)(bdc)(3)(DMF)(4) (1) and M-U(2)Cl(2)(bdc)(3)(DMF)(4) (2) has been identified at low temperature (100-110 °C) for bdc/U = 1-4 (bdc = terephthalate linker). Their structures are built up from isolated uranium centers in nine-fold coordination, surrounded by 6 carboxyl oxygen atoms, 2 oxygen atoms coming from DMF molecules and one chlorine atom. The uranium cations are linked to each other through the bdc ligand in order to generate a 3D framework. By increasing the temperature (130-150 °C), a layered like compound has been isolated, U(2)(bdc)(4)(DMF)(4) (3). It is composed of discrete actinide centers in ten-fold coordination, with 8 carboxyl oxygen atoms and 2 oxygen atoms from DMF molecules. The connection of the UO10 units with the bdc linkers generates 2D sheets. When a controlled amount of water is added to the reaction medium, the crystallization of the UiO-66-like U(6)O(4)(OH)(4)(H(2)O)(6)(bdc)(6)·10DMF solid (containing a hexanuclear sub-unit) is observed for temperature 110-120 °C and the H(2)O/U molar ratio in the range of 2-10. At higher temperature (140-150 °C), a distinct phase appeared, U(2)O(2)(bdc)(2)(DMF) (4), which consists of infinite chains of uranium centers, linked to each other via the bdc ligands. Higher water contents led to the formation of urania UO(2). PMID:25428593
Nanoscale coordination polymers for anticancer drug delivery
NASA Astrophysics Data System (ADS)
Phillips, Rachel Huxford
This dissertation reports the synthesis and characterization of nanoscale coordination polymers (NCPs) for anticancer drug delivery. Nanoparticles have been explored in order to address the limitations of small molecule chemotherapeutics. NCPs have been investigated as drug delivery vehicles as they can exhibit the same beneficial properties as the bulk metal-organic frameworks as well as interesting characteristics that are unique to nanomaterials. Gd-MTX (MTX = methotrexate) NCPs with a MTX loading of 71.6 wt% were synthesized and stabilized by encapsulation within a lipid bilayer containing anisamide (AA), a small molecule that targets sigma receptors which are overexpressed in many cancer tissues. Functionalization with AA allows for targeted delivery and controlled release to cancer cells, as shown by enhanced efficacy against leukemia cells. The NCPs were doped with Ru(bpy)32+ (bpy = 2,2'-bipyridine), and this formulation was utilized as an optical imaging agent by confocal microscopy. NCPs containing the chemotherapeutic pemetrexed (PMX) were synthesized using different binding metals. Zr-based materials could not be stabilized by encapsulation with a lipid bilayer, and Gd-based materials showed that PMX had degraded during synthesis. However, Hf-based NCPs containing 19.7 wt% PMX were stabilized by a lipid coating and showed in vitro efficacy against non-small cell lung cancer (NSCLC) cell lines. Enhanced efficacy was observed for formulations containing AA. Additionally, NCP formulations containing the cisplatin prodrug disuccinatocisplatin were prepared; one of these formulations could be stabilized by encapsulation within a lipid layer. Coating with a lipid layer doped with AA rendered this formulation an active targeting agent. The resulting formulation proved more potent than free cisplatin in NSCLC cell lines. Improved NCP uptake was demonstrated by confocal microscopy and competitive binding assays. Finally, a Pt(IV) oxaliplatin prodrug was synthesized and incorporated in different NCPs using various binding metals. A moderate drug loading of 44.9 wt% was determined for Zr-based NCPs. This drug loading, along with a diameter less than 200 nm, make these particles promising candidates for further stabilization via lipid encapsulation.
NASA Astrophysics Data System (ADS)
Babu, Chatla Naga; Suresh, Paladugu; Sampath, Natarajan; Prabusankar, Ganesan
2014-10-01
Two one-dimensional (1D) coordination polymers, [{LCd(O2NO)2(DMF)2}2{(LCd(O2NO)2(DMF))(DMF)}2]n (1) and [L?Cd(O2NO)(ONO2)(DMF)2]n (2), having an aryl chromophoric unit and a flexible bis(imidazole) tail, 9,10-bis{(benzimidazol)methyl}anthracene (L) and 1,4-bis{(imidazol)methyl}benzene (L?), with various coordination modes have been obtained. Molecule 1 represents the first structurally characterized one dimensional coordination polymer consisting of both hepta- and octa-coordinated cadmium centers. In 1, two distorted pentagonal bipyramidal Cd(II) centers and two distorted triangular dodecahedral Cd(II) centers are alternately arranged via bridging bidentate N,N-chelating ligand, L. Whereas, a distorted pentagonal bipyramidal Cd(II) center is formed in 2 where the sterically less crowded L? serves as a bridging bidentate N,N-chelating ligand. Furthermore, 1 and 2 have been characterized by elemental analysis, FT-IR, 1H NMR, UV-vis and fluorescent techniques.
Mixing of immiscible polymers using nanoporous coordination templates
Uemura, Takashi; Kaseda, Tetsuya; Sasaki, Yotaro; Inukai, Munehiro; Toriyama, Takaaki; Takahara, Atsushi; Jinnai, Hiroshi; Kitagawa, Susumu
2015-01-01
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. PMID:26130294
NASA Astrophysics Data System (ADS)
Suo, Tongchuan; Whitmore, Mark D.
2014-11-01
We examine end-tethered polymers in good solvents, using one- and three-dimensional self-consistent field theory, and strong stretching theories. We also discuss different tethering scenarios, namely, mobile tethers, fixed but random ones, and fixed but ordered ones, and the effects and important limitations of including only binary interactions (excluded volume terms). We find that there is a "mushroom" regime in which the layer thickness is independent of the tethering density, ?, for systems with ordered tethers, but we argue that there is no such plateau for mobile or disordered anchors, nor is there one in the 1D theory. In the other limit of brushes, all approaches predict that the layer thickness scales linearly with N. However, the ?1/3 scaling is a result of keeping only excluded volume interactions: when the full potential is included, the dependence is faster and more complicated than ?1/3. In fact, there does not appear to be any regime in which the layer thickness scales in the combination N?1/3. We also compare the results for two different solvents with each other, and with earlier ? solvent results.
Zhu, Yuan-Yuan; Zhu, Ming-Sheng; Yin, Ting-Ting; Meng, Yin-Shan; Wu, Zong-Quan; Zhang, Yi-Quan; Gao, Song
2015-04-20
A one-dimensional cobalt(II) coordination polymer, [Co(btm)2(SCN)2·H2O]n [btm = bis(1H-1,2,4-triazol-1-yl)methane], was synthesized and magnetically characterized. The isolated slightly distorted octahedral Co(II) ion displays field-induced slow relaxation with a big positive axial and a negative rhombic magnetic anisotropy (D = 93.9 cm(-1) and E = -10.5 cm(-1)), and the anisotropy energy barrier is 45.4 K. PMID:25853410
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.
{[GdAg 2(dtpa)(H 2O)] · 3H 2O} n : the first 2D Gd–Ag coordination polymer with Ag–Ag interaction
Bin Zhao; Xiao-Yan Chen; Wen-Zhen Wang; Peng Cheng; Bin Ding; Dai-Zheng Liao; Shi-Ping Yan; Zong-Hui Jiang
2005-01-01
A novel 4d–4f coordination polymer {[GdAg2(dtpa)(H2O)]·3H2O}n (1) (dtpa=diethylenetriamine pentaacetate) was synthesized and characterized by magnetic and EPR studies. Its one-dimensional Gd–Ag ladder-like chains built upon tetranuclear rings are further connected by Ag–O bonds and Ag–Ag interactions to form a lamellar 2D packing.
NASA Astrophysics Data System (ADS)
Ar?c?, Mürsel; Ye?ilel, Okan Zafer; Ye?ilöz, Ye?im; ?ahin, Onur
2014-12-01
Four new coordination polymers, namely, {Hemim·[Ag(Hssa)(H2O)]}n (1), {[Ag(ina)2 Ag(Hssa)]·CH3OH·H2O}n (2), {[Ag2(Hssa)(dmp)1.5]·2H2O}n (3) and [Ag2(Hssa)(daoc)]n (4) (Hssa: 5-Sulfosalicylate, emim: 2-ethyl-4-methylimidazole, ina: isonicotinamide, dmp: 2,5-dimethylpyrazine and daoc: 1,8-diaminooctane) were synthesized and characterized by IR spectroscopy, elemental analysis, single crystal X-ray diffraction, powder X-ray diffraction (PXRD) and thermal analysis techniques. Complexes 1 and 2 are one-dimensional (1D) coordination polymers while complexes 3 and 4 are three-dimensional (3D) coordination polymers. Complex 3 consists of three dimensional (3D) 3,3,6-c net with 3,3,6T37 topology. Complex 4 exhibits a 2-fold interpenetrating 3D framework with tfc topology. Complexes 1-4 contain ligand-supported (1-3) and unsupported (4) argentophilic Ag⋯Ag interactions. Photoluminescence spectra of the complexes demonstrate that photoluminescent properties may be attributed to intraligand transition of coordinated Hssa ligand.
Wright, James S.; Vitórica-Yrezábal, Iñigo J.; Adams, Harry; Thompson, Stephen P.; Hill, Adrian H.; Brammer, Lee
2015-01-01
A family of one-dimensional coordination polymers, [Ag4(O2C(CF2)2CF3)4(phenazine)2(arene)n]·m(arene), 1 (arene = toluene or xylene), have been synthesized and crystallographically characterized. Arene guest loss invokes structural transformations to yield a pair of polymorphic coordination polymers [Ag4(O2C(CF2)2CF3)4(phenazine)2], 2a and/or 2b, with one- and two-dimensional architectures, respectively. The role of pre-organization of the polymer chains of 1 in the selectivity for formation of either polymorph is explored, and the templating effect of toluene and p-xylene over o-xylene or m-xylene in the formation of arene-containing architecture 1 is also demonstrated. The formation of arene-free phase 2b, not accessible in a phase-pure form through other means, is shown to be the sole product of loss of toluene from 1-tol·tol [Ag4(O2C(CF2)2CF3)4(phenazine)2(toluene)]·2(toluene), a phase containing toluene coordinated to Ag(I) in an unusual ?:?1,?1 manner. Solvent-vapour-assisted conversion between the polymorphic coordination polymers and solvent-vapour influence on the conversion of coordination polymers 1 to 2a and 2b is also explored. The transformations have been examined and confirmed by X-ray diffraction, NMR spectroscopy and thermal analyses, including in situ diffraction studies of some transformations. PMID:25866656
Wright, James S; Vitórica-Yrezábal, Iñigo J; Adams, Harry; Thompson, Stephen P; Hill, Adrian H; Brammer, Lee
2015-03-01
A family of one-dimensional coordination polymers, [Ag4(O2C(CF2)2CF3)4(phenazine)2(arene) n ]·m(arene), 1 (arene = toluene or xylene), have been synthesized and crystallographically characterized. Arene guest loss invokes structural transformations to yield a pair of polymorphic coordination polymers [Ag4(O2C(CF2)2CF3)4(phenazine)2], 2a and/or 2b , with one- and two-dimensional architectures, respectively. The role of pre-organization of the polymer chains of 1 in the selectivity for formation of either polymorph is explored, and the templating effect of toluene and p-xylene over o-xylene or m-xylene in the formation of arene-containing architecture 1 is also demonstrated. The formation of arene-free phase 2b , not accessible in a phase-pure form through other means, is shown to be the sole product of loss of toluene from 1-tol·tol [Ag4(O2C(CF2)2CF3)4(phenazine)2(toluene)]·2(toluene), a phase containing toluene coordinated to Ag(I) in an unusual ?:?(1),?(1) manner. Solvent-vapour-assisted conversion between the polymorphic coordination polymers and solvent-vapour influence on the conversion of coordination polymers 1 to 2a and 2b is also explored. The transformations have been examined and confirmed by X-ray diffraction, NMR spectroscopy and thermal analyses, including in situ diffraction studies of some transformations. PMID:25866656
NASA Astrophysics Data System (ADS)
Salik, Boaz; Rosen, Joseph; Yariv, Ammon
1995-08-01
A general method is presented of optimizing one-dimensional holograms to realize an arbitrary diffracted field distribution over the propagation volume. A computationally simpler approach is developed for the case in which only the transverse distribution in one plane and the longitudinal distribution on one axis are of interest. Scaling effects in the optimized beams are studied and compared with those of canonical beams.
Johannes Voit; Theoretische Physik
1995-01-01
I attempt to give a pedagogical overview of the progress which has occurred during the past decade in the description of one-dimensional correlated fermions. Fermi liquid theory based on a quasi-particle picture, breaks down in one dimension because of the Peierls divergence and because of charge-spin separation. It is replaced by a Luttinger liquid whose elementary excitations are collective charge
NASA Astrophysics Data System (ADS)
Marandi, Farzin; Amoopour, Fariba; Pantenburg, Ingo; Meyer, Gerd
2010-06-01
The two lead(II) coordination polymers [Pb(4,4'-dm-2,2'-bpy)(Dca)(NO 3)] n ( 1) and [Pb(4,4'-dmo-2,2'-bpy)(Dca)(NO 3)] n ( 2) were prepared by treatment of lead(II) nitrate, sodium dicyanamide with 4,4'-dimethyl-2,2'-bipyridine and 4,4'-dimethoxy-2,2'-bipyridine, respectively. Both polymers were characterized by elemental analysis, IR and 1H NMR spectroscopy, thermogravimetric analysis and X-ray crystallography. The coordination polymers can be described as one-dimensional double-chains with Pb(II) centers bridged by Dca and nitrate co-ligands, containing trinuclear rings, [Pb 3(L) 3(NO 3) 2(Dca)], and bridging nitrate and Dca co-ligands in cis and trans positions, respectively. The coordination number of the Pb(II) ions in 1 and 2 is seven, with the PbN 4O 3 coordination polyhedron containing a stereochemically active lone pair of electrons with hemi-directed coordination spheres. The polymer chains form networks via supramolecular interactions that include O⋯O, C sbnd H⋯O, C sbnd H⋯N interactions, in addition to hydrogen bonding and ?-? stacking.
One-dimensional silicone nanofilaments.
Artus, Georg R J; Seeger, Stefan
2014-07-01
A decade ago one-dimensional silicone nanofilaments (1D-SNF) such as fibres and wires were described for the first time. Since then, the exploration of 1D-SNF has led to remarkable advancements with respect to material science and surface science: one-, two- and three-dimensional nanostructures of silicone were unknown before. The discovery of silicone nanostructures marks a turning point in the research on the silicone material at the nanoscale. Coatings made of 1D-SNF are among the most superhydrophobic surfaces known today. They are free of fluorine, can be applied to a large range of technologically important materials and their properties can be modified chemically. This opens the way to many interesting applications such as water harvesting, superoleophobicity, separation of oil and water, patterned wettability and storage and manipulation of data on a surface. Because of their high surface area, coatings consisting of 1D-SNF are used for protein adsorption experiments and as carrier systems for catalytically active nanoparticles. This paper reviews the current knowledge relating to the broad development of 1D-SNF technologies. Common preparation and coating techniques are presented along with a comparison and discussion of the published coating parameters to provide an insight on how these affect the topography of the 1D-SNF or coating. The proposed mechanisms of growth are presented, and their potentials and shortcomings are discussed. We introduce all explored applications and finally identify future prospects and potentials of 1D-SNF with respect to applications in material science and surface science. PMID:24742356
Li, Jing
, Crystal Structure, and Magnetic and Thermal Properties of 2 [MCl2(4,4-bipyridine)] (M ) Fe, Co, Ni, Co in the field-dependent magnetization measurement for all four compounds. The magnetic properties observed metal species (3.6 Å). Studies on magnetic properties have been reported on a number of compounds
Himangshu Deka; Rupam Sarma; Satchi Kumari; Alika Khare; Jubaraj B. Baruah
2011-01-01
Dicarboxylate coordination polymers (1–5) of Mn(II), Ni(II), Cu(II), Zn(II) and Cd(II), respectively, derived from (7-carboxymethoxy-naphthalen-2-yloxy)-acetic acid (L1H2) are synthesized and characterized. Depending on the coordination sites around the metal centers and coordination mode of the ligand, dimensionality of these polymers varies. The dicarboxylates adopt three spatial orientations: in-plane linear coordination, out-of-plane cis coordination and out-of-plane trans coordination mode. Both the
A mixed-valence copper coordination polymer generated by hydrothermal metal/ligand redox reactions
Li, Jing
A mixed-valence copper coordination polymer generated by hydrothermal metal/ligand redox reactions A novel coordination polymer of mixed-valence copper(I,II) with 4,4A-bipyridine and in situ oxidized and crystallographically char- acterized to be a laminated structure via weak copper(II) oxygen interactions. Extended
Gao, Song
Syntheses, structures and magnetic properties of 1-D coordination polymers containing both region. Magnetic susceptibilities of 1 and 2 were mea- sured by using an Oxford MagLab 2000 magnetometer Abstract Structures of two 1-D coordination polymers, [MII pyr2NCN22] (M Mn (1), Co (2), pyr 2
Fast Algorithms for One-Dimensional Compaction with Jog Insertion
Matthias F. M. Stallmann; Thomas A. Hughes
1993-01-01
Introduction. The one-dimensional channel compaction problem with automaticjog insertion may be described informally as follows. We are given n horizontalwire segments organized into t tracks. Segments on the same track have the samey-coordinate and the ranges of their x-coordinates do not overlap. Each segment hasa via at each end, connecting it to vertical wires on another layer. The goal is
Ni, Jia; Wei, Kai-Ju; Min, Yuanzeng; Chen, Yaowen; Zhan, Shunze; Li, Dan; Liu, Yangzhong
2012-05-01
Reactions of CuX (X = Br(-), I(-) or CN(-)) with various types of 2,2'-dipyridylamine (dpa) derivatives have been performed via a hydrothermal-solvothermal method and the products have been structurally characterized by X-ray crystallography. Four ligands with different coordination motifs were employed in the reactions, including angular N,N,N',N'-tetra(2-pyridyl)-2,6-pyridinediamine (tppda); linear N,N,N',N'-tetra(2-pyridyl)-1,4-phenylenediamine (tppa) and N,N,N',N'-tetra(2-pyridyl)biphenyl-4,4'-diamine (tpbpa); and star-shaped tris-[4-(2,2'-dipyridylamino)-phenyl]amine (tdpa), which yielded eight copper(I) complexes exhibiting different stoichiometries of Cu-dpa and variable coordination modes of dpa. The compound [Cu(2)(tppda)(?-I)(2)](n) (1) forms a one dimensional (1D) coordination polymer exclusively through double ?(2)-I bridges, which arranges to two dimensional (2D) metal-organic frameworks (MOFs) via the face-to-face ?···? stacking interactions from pyridyl rings. The compound [Cu(6)(tppa)(?(3)-Br)(6)](n) (2) forms a 2D network linked through multiple ?(3)-Br bridges. The compound [Cu(2)(tppa)(?-CN)(2)](n) (3) is also a 2D MOF containing 1D (CuCN)(n) chains. The compounds [Cu(tpbpa)Br](n) (4) and [Cu(4)(tpbpa)(2)(?-I)(4)](n) (5) display two different 1D assemblies: a zig-zag chain for 4 and a linear structure for 5. The compound [Cu(4)(tpbpa)(?-CN)(4)](n) (6) shows a pseudo-4,8(2) topological net, while the compound [Cu(8)(tpbpa)(?-CN)(8)](n)·2nH(2)O (7) exhibits a three-dimensional (3D) framework containing a ···PM··· double helical structure, although both of them contain (CuCN)(n) chains. The compound [Cu(2)(tdpa)(?-I)(2)](n) (8) is a zig-zag chain based on the star-shaped molecule tpda, in which one of three dpa-arms is free of coordination to metal ions. All complexes exhibit luminescence in the solid state. PMID:22415529
Bisht, Kamal Kumar; Rachuri, Yadagiri [Analytical Discipline and Centralized Instrument Facility, CSIR—Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial Research, G. B. Marg, Bhavnagar-364 002, Gujarat (India); Academy of Scientific and Innovative Research (AcSIR), CSIR—Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial Research, G. B. Marg, Bhavnagar-364 002, Gujarat (India); Parmar, Bhavesh [Analytical Discipline and Centralized Instrument Facility, CSIR—Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial Research, G. B. Marg, Bhavnagar-364 002, Gujarat (India); Suresh, Eringathodi, E-mail: esuresh@csmcri.org [Analytical Discipline and Centralized Instrument Facility, CSIR—Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial Research, G. B. Marg, Bhavnagar-364 002, Gujarat (India); Academy of Scientific and Innovative Research (AcSIR), CSIR—Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial Research, G. B. Marg, Bhavnagar-364 002, Gujarat (India)
2014-05-01
Four ternary coordination polymers (CPs) namely, ([Ni(SDB)(BITMB)(H{sub 2}O)]·H{sub 2}O){sub n} (CP1), ([Cd(SDB)(BITMB) (H{sub 2}O)]·(THF)(H{sub 2}O)){sub n} (CP2), ([Zn{sub 2}(SDB){sub 2}(BITMB)]·(THF){sub 2}){sub n} (CP3) and ([Co{sub 2}(SDB){sub 2}(BITMB)]·(Dioxane){sub 3}){sub 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 ??? 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. - Graphical abstract: Four new ternary transition metal CPs have been hydrothermally prepared and their structural aspects as well as photocatalytic activity for decolourization of metanil yellow (MY) dye have been investigated. - Highlights: • Four ternary coordination polymers containing Ni, Cd, Zn and Co center are prepared. • Crystal structure and thermal stability of all four CPs has been described. • PL and diffuse reflectance spectra of synthesized CPs have also been examined. • Band gap values suggest semiconducting behavior of prepared CPs. • Photocatalytic activity of CPs for oxidative degradation of metanil yellow is studied.
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 ?⋯? 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.
Structural Design Parameters for Highly Birefringent Coordination Polymers.
Thompson, John R; Katz, Michael J; Williams, Vance E; Leznoff, Daniel B
2015-07-01
A series of coordination polymer materials incorporating the highly anisotropic 2-(2-pyridyl)-1,10-phenanthroline (phenpy) building block have been synthesized and structurally characterized. M(phenpy)[Au(CN)2]2 (M = Cd, Mn) are isostructural and form a 1-D chain through bridging [Au(CN)2](-) units and extend into a 2-D sheet through aurophilic interactions. M(phenpy)(H2O)[Au(CN)2]2·2H2O (M = Cd, Mn, and Zn) are also isostructural but differ from the first set via the inclusion of a water molecule into the coordination sphere, resulting in a 1-D topology through aurophilic interactions. In(phenpy)(Cl)2[Au(CN)2]·0.5H2O forms a dimer through bridging chlorides and contains a free [Au(CN)2](-) unit. In the plane of the primary crystal growth direction, the birefringence values (?n) of 0.37(2) (Cd(phenpy)[Au(CN)2]2), 0.50(3) (In(phenpy)(Cl)2[Au(CN)2]·0.5H2O), 0.56(3) and 0.59(6) (M(phenpy)(H2O)[Au(CN)2]2·2H2O M = Cd and Zn, respectively) were determined. ?, a structural parameter defined by phenpy units rotated in the A-C plane relative to the light propagation (C) direction, was found to correlate to ?n magnitudes. The addition of a carbon-carbon double bond to terpy has increased the molecular polarizability anisotropy of the building block, and all structures have reduced deviation from planarity in comparison to terpy and terpy derivative structures, leading to these higher ?n values, which are among the highest reported for crystalline solids. PMID:26098267
Deka, Himangshu; Sarma, Rupam [Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781 039, Assam (India); Kumari, Satchi; Khare, Alika [Department of Physics, Indian Institute of Technology Guwahati, Guwahati 781 039, Assam (India); Baruah, Jubaraj B., E-mail: juba@iitg.ernet.in [Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781 039, Assam (India)
2011-07-15
Dicarboxylate coordination polymers (1-5) of Mn(II), Ni(II), Cu(II), Zn(II) and Cd(II), respectively, derived from (7-carboxymethoxy-naphthalen-2-yloxy)-acetic acid (L{sub 1}H{sub 2}) are synthesized and characterized. Depending on the coordination sites around the metal centers and coordination mode of the ligand, dimensionality of these polymers varies. The dicarboxylates adopt three spatial orientations: in-plane linear coordination, out-of-plane cis coordination and out-of-plane trans coordination mode. Both the cis and trans out-of-plane coordination modes are found to exist only if the ancillary ligand pyridine is coordinated to the metal ion. When the aquoligand coordinates the in-plane linear coordination mode of L{sub 1} predominates. The coordination polymers 4 and 5 show photoluminescence in solution. The dicarboxylate of (5-carboxymethoxy-naphthalen-1-yloxy)-acetic acid (L{sub 2}H{sub 2}) does not form coordination polymer under ambient conditions, but prefers to remain as uncoordinated anion providing hydrophobic confinement to hexa-aquometal(II) cation. Compound 3 crystallizes in P2{sub 1} space group and it shows broadband ultra-violet fluorescence centered at 352.9 nm on focusing 632.8 nm He:Ne laser. - Graphical abstract: Different geometrical arrangements in coordination polymers derived from (7-carboxymethoxy-naphthalen-2-yloxy)-acetic acid of metal ions Mn(II), Ni(II), Cu(II), Zn(II) and Cd(II) are presented. The (5-carboxymethoxy-naphthalen-1-yloxy)-acetic acid led to hexa-aquo cadmium(II) dicarboxylate. Highlights: > Structural and spectroscopic characterizations of five dicarboxylate coordination polymers of (7-carboxymethoxy-naphthalen-2-yloxy)-acetic acid with different metal ions are presented. > Different geometrical arrangements of coordination polymers stabilized in solid state are described. > Photoluminescence properties of the polymers are shown. > NLO property of a copper coordination polymer is described.
Ghoneim, M M; El-Sonbati, A Z; El-Bindary, A A; Diab, M A; Serag, L S
2015-04-01
A number of novel polymer complexes of various anions of copper(II), cobalt(II), nickel(II) and uranyl(II) with N(4-(acrylamido)-2-hydroxy benzoic acid) (ABH) have been synthesized and characterized by elemental analysis, IR, 1H NMR, magnetic susceptibility measurements, electronic spin resonance, vibrational spectra and thermal analysis. The molecular structures of the ligand are optimized theoretically and the quantum chemical parameters are calculated. Tentative structures for the polymeric metal complexes due to their potential application are also suggested. The IR data exhibit the coordination of ONO2/OAc/SO4 with the metal ions in the polymeric metal complex. Vibrational spectra indicate coordination of carboxylate oxygen and phenolic OH of the ligand giving a MO4 square planar chromophore. Ligand field ESR spectra support square planar geometry around Cu(II). The thermal decomposition of the polymer complexes were discussed in relation to structure, and the thermodynamic parameters of the decomposition stages were evaluated applying Coast-Redfern and Horowitz-Metzger methods. PMID:25589393
NASA Astrophysics Data System (ADS)
Ghoneim, M. M.; El-Sonbati, A. Z.; El-Bindary, A. A.; Diab, M. A.; Serag, L. S.
2015-04-01
A number of novel polymer complexes of various anions of copper(II), cobalt(II), nickel(II) and uranyl(II) with N(4-(acrylamido)-2-hydroxy benzoic acid) (ABH) have been synthesized and characterized by elemental analysis, IR, 1H NMR, magnetic susceptibility measurements, electronic spin resonance, vibrational spectra and thermal analysis. The molecular structures of the ligand are optimized theoretically and the quantum chemical parameters are calculated. Tentative structures for the polymeric metal complexes due to their potential application are also suggested. The IR data exhibit the coordination of ONO2/OAc/SO4 with the metal ions in the polymeric metal complex. Vibrational spectra indicate coordination of carboxylate oxygen and phenolic OH of the ligand giving a MO4 square planar chromophore. Ligand field ESR spectra support square planar geometry around Cu(II). The thermal decomposition of the polymer complexes were discussed in relation to structure, and the thermodynamic parameters of the decomposition stages were evaluated applying Coast-Redfern and Horowitz-Metzger methods.
Culp, Jeffrey T; Sui, Lang; Goodman, Angela; Luebke, David
2013-03-01
Mixed matrix membranes (MMMs) comprised of metal organic frameworks (MOFs) dispersed in organic polymers are popular materials under study for potential applications in gas separations. However, research on MMMs containing structurally dynamic sorbents known as flexible MOFs has only very recently appeared in the literature. The thermodynamic requirements of the structure transition between the low porosity and high porosity phases of flexible MOFs may provide a mechanism for high adsorption selectivity in these materials. A fundamental question in MMMs containing flexible MOFs is how the constraint of the polymer matrix on the intrinsic expansion of the flexible MOF particles that occurs during gas adsorption might affect the thermodynamics of this structural phase transition and influence the gas adsorption properties of the embedded MOF. To investigate the fundamental nature of this flexible MOF-polymer interface, thin films of ~20 um thickness were prepared using the flexible linear chain coordination polymer catena-bis(dibenzoylmethanato)-(4,4'bipyridyl)nickel(II) "Ni(Bpy)(DBM)(2)" embedded as 35 wt% dispersions in Matrimid®, polystyrene, and polysulfone. The adsorption of CO(2) in the polymers and embedded particles was studied using in situ ATR-FTIR spectroscopy and variable temperature volumetric CO(2) adsorption/desorption isotherms. Interestingly, no effect of the polymer matrix on the gas adsorption behavior of the embedded Ni(Bpy)(DBM)(2) particles was observed. The composite samples all showed the same threshold pressures for CO(2) absorption and desorption hysteresis associated with the structural phase change in the polymer embedded Ni(Bpy)(DBM)(2) particles as was observed in the pristine polycrystalline sample. The current results contrast those recently reported for a MMM containing the flexible MOF "NH(2)-MIL-53" where a significant increase in the threshold pressure for CO(2) adsorption associated with the structural phase change of the MOF was observed in the MMM as compared to the isolated MOF. The conflicting behaviors in these two systems are rationalized from the large differences in unit cell expansions between the two MOFs during the CO(2) adsorption process. PMID:23168045
Bing Yan; Qi-You Xie
2003-01-01
One novel dysprosium coordination polymer [Dy(PIC)3(H2O)2]n (HPIC = pyridine-4-carboxylic acid) has been synthesized. X-ray analysis reveals that it forms the chain-like molecular structure through the bridged oxygen atoms of the carbonyl groups. The title coordination polymer crystallizes in the monoclinic system, space group C2\\/c, with lattice parameters: a=20.243(9) Å, b=11.576(5) Å, c=9.834(4) Å, ?=110.601(2)°, V=2078(2) Å3, Dc=1.805 mg\\/m3, Z=4, F(000)=1100,
Gao, Song
bonding, resulting in a 3-D supramolecular architecture. Magnetic susceptibility studies reveal reserved. Keywords: Hydrothermal synthesis; Coordination polymer; Magnetic property; Transition metal analysis was performed with a ZRY-2P Thermal Analyzer. The magnetic susceptibility measurements were
NASA Astrophysics Data System (ADS)
Han, Li-Juan; Kong, Ya-Jie; Sheng, Ning
2015-01-01
A new one-dimensional (1D) coordination polymer, [Cd(NPTA)(1,10-phen)(H2O)] n ( 1) (H2NPTA = 4-nitrophthalic acid; 1,10-phen = 1,10-phenanthroline monohydrate), has been synthesized under hydrothermal conditions and characterized by elemental analysis, single-crystal X-ray diffraction, solid state emission spectra, FT-IR spectra, and thermogravimetric analyses. The compound belongs to triclinic system with space group , and exhibits a one-dimensional linear chain. Each Cd with a strongly distorted octahedral coordination geometry is six-coordinated by two N atoms from one 1,10-phenanthroline ligand, three O atoms from two carboxylate groups of two different NPTA2- ligands and one O atoms from lattice water. Layer supramolecular architecture is formed by medium ?-? stacking interactions between two neighboring phenanthroline rings from two independent linear chains. Studies on luminescent property of 1 exhibit the solid state emission originating from an intra ligand ? ? ?* transition of NPTA2- ligand.
Ma, Qi; Zhu, Miaoli; Lu, Liping; Feng, Sisi; Wang, Tianwei
2010-07-01
Three new coordination polymers ([Mn(3)(dctrz)(2)(H(2)O)(8)](n) (1), [Co(Hdctrz)(H(2)O)(3)](n) (2) and [Cd(Hdctrz)(H(2)O)(2)](n) (3), H(3)dctrz, 1-H-1,2,4-triazole-3,5-dicarboxylic acid) based on the self-assembly of Mn(2+), Co(2+) and Cd(2+) ions with H(3)dctrz have been synthesized and characterized by single crystal X-ray diffraction analysis. Variable temperature magnetic studies are investigated for complexes 1 and 2. Complex 1 is assembled into a one-dimensional molecular chain via trinuclear units formed from two dctrz anion bridges and eight coordination waters. In 2, the central Co(2+) cations with six-coordinated octahedron geometry are bridged by Hdctrz anions to form one-dimensional zigzag chain structures. Complex 3 displays a 2D rhombus grid-like architecture with a (4, 4) topology, achieved through Hdctrz anion bridges. Both complexes 1 and 2 exhibit S = 5/2 (Mn(2+)) and S = 3/2 (Co(2+)) spin Heisenberg chains with alternating and regular magnetic sequences. Variable temperature (1.8-300 K) magnetic studies indicate weak antiferromagnetic coupling between the metal centres in complexes 1 and 2. PMID:20505855
Angulo, Beatriz; García, José I; Herrerías, Clara I; Mayoral, José A; Miñana, Ana C
2012-07-01
An efficient release-capture strategy for the recovery and reuse of enantioselective catalysts in the Henry reaction is described. This strategy is based on the precipitation of an insoluble coordination polymer at the end of each reaction, allowing easy separation from products. The coordination polymer is formed through aggregation of Cu(II) ions with ditopic bisoxazoline-based chiral ligands. Up to 11 catalytic cycles have been conducted keeping good yields and enantioselectivities. PMID:22667829
NASA Astrophysics Data System (ADS)
Mahmudov, Kamran T.; Haukka, Matti; Sutradhar, Manas; Mizar, Archana; Kopylovich, Maximilian N.; Pombeiro, Armando J. L.
2013-02-01
Reaction of 2-(2-(2,4-dioxopentan-3-ylidene)hydrazinyl)benzenesulfonic acid (H2L) with copper(II) nitrate hydrate in the presence of pyrazine (pz) in methanol affords the coordination polymer [Cu2(?-L)2(H2O)2(?-pz)]n (1), where the bidentate pz molecule links two Cu(II) centres of two different dimeric units, giving rise to a one-dimensional chain. The dimeric unit [Cu2(?-L)2(H2O)2] consists of two distorted octahedral Cu(II) centres connected via oxygen atoms of the sulfo group of the bridging L2- ligand. The extensive hydrogen bonding between the coordinated water and pz molecules leads to the formation of a supramolecular 3D associate. Compound 1 has been characterized by elemental analysis, ESI-MS, IR spectroscopy and single-crystal X-ray diffraction analysis.
One-dimensional gas of hard needles
Kardar, Mehran
We study a one-dimensional gas of needlelike objects as a testing ground for a formalism that relates the thermodynamic properties of “hard” potentials to the probabilities for contacts between particles. Specifically, we ...
One dimensional representations in quantum optics
NASA Technical Reports Server (NTRS)
Janszky, J.; Adam, P.; Foldesi, I.; Vinogradov, An. V.
1993-01-01
The possibility of representing the quantum states of a harmonic oscillator not on the whole alpha-plane but on its one dimensional manifolds is considered. It is shown that a simple Gaussian distribution along a straight line describes a quadrature squeezed state while a similar Gaussian distribution along a circle leads to the amplitude squeezed state. The connection between the one dimensional representations and the usual Glauber representation is discussed.
Mechanical Properties of One-Dimensional Nanostructures
Gheorghe Stan; Robert F. Cook
2010-01-01
The elastic mechanical properties of one-dimensional nanostructures are considered, with an emphasis on the use of contact-resonance\\u000a atomic force microscopy methods to determine elastic moduli. Various methods used to determine elastic moduli of one-dimensional\\u000a nanostructures are reviewed before detailed consideration of the experimental and analytical methods used in contact-resonance\\u000a atomic force microscopy As direct applications of contact-resonance atomic force microscopy
Factorizations of one-dimensional classical systems
NASA Astrophysics Data System (ADS)
Kuru, ?engül; Negro, Javier
2008-02-01
A class of one-dimensional classical systems is characterized from an algebraic point of view. The Hamiltonians of these systems are factorized in terms of two functions that together with the Hamiltonian itself close a Poisson algebra. These two functions lead directly to two time-dependent integrals of motion from which the phase motions are derived algebraically. The systems so obtained constitute the classical analogues of the well known factorizable one-dimensional quantum mechanical systems.
A click chemistry based coordination polymer inside small heat shock protein.
Lucon, Janice; Abedin, Md Joynal; Uchida, Masaki; Liepold, Lars; Jolley, Craig C; Young, Mark; Douglas, Trevor
2010-01-14
A branched iron-phenanthroline based coordination polymer has been constructed in a water based system using a click chemistry approach to link monomeric coordination complexes together within a protein cage nanoarchitecture, which acts both as a template and a sized constrained reaction environment. PMID:20024346
Ramaswamy, Padmini; Matsuda, Ryotaro; Kosaka, Wataru; Akiyama, George; Jeon, Hyung Joon; Kitagawa, Susumu
2014-02-01
Three new sulfonated porous coordination polymers (PCPs)/metal-organic frameworks (MOFs) have been synthesized using solvothermal methods. These PCPs possess porous structures with non-coordinating sulfonic acid groups or sulfonate with dimethyl ammonium cations and exhibit high proton conductivity at a low humidity of 60% RH (relative humidity) at ambient temperature. PMID:24322717
A novel one-dimensional chain built of vanadyl ions and pyrazine-2,5-dicarboxylate.
Lankelma, Marianne; de Boer, Jeroen; Ferbinteanu, Marilena; Dantas Ramos, André Luis; Tanasa, Radu; Rothenberg, Gadi; Tanase, Stefania
2015-07-01
We present a new coordination polymer, {[VO(pzdc)(H2O)2] H2O}n, built from vanadyl and pyrazine-2,5-dicarboxylate (pzdc) ions. It consists of a one-dimensional chain of vanadyl ions linked by pzdc ions. The carboxylate groups show monodentate coordination, while the pyrazine ring is present both in non-coordinated and coordinated modes. This novel structure is stabilized by an intricate network of hydrogen bonds. The material is highly robust, and thermally stable up to 400 K. It is also antiferromagnetic, with a maximum magnetic susceptibility at ca. 50 K. The orbital shape and population analysis by means of DFT analysis confirm the ?-acceptor role of the aromatic nitrogen function of the ligand, while the oxygen-based moieties (carboxylates from pzdc, the aqua ligands and oxo from V[double bond, length as m-dash]O group) behave as normal donors. Charting the density flow related with significant transitions computed by time-dependent DFT, we determined the ligand-to-metal charge transfer processes. The topology of the chain complex implies two different types of connecting bridges. Using Broken Symmetry DFT modelling gives evidence for two different exchange coupling mechanisms between the vanadyl ions along each of these two molecular bridges. One is strongly antiferromagnetic, practically reducing the chain to 'vanadyl dimers'. The other is almost uncoupled, due to the large distance between the vanadyl ions. PMID:26014716
New Coordination Polymers Based on Transition Metal Squarates and Pyrazine Ligands
Christian Näther; Jan Greve
2003-01-01
Three new coordination polymers have been prepared by hydrothermal reaction of squaric acid, pyrazine and the metal halides FeCl2· 4H 2O, CoBr2 and NiBr2. In their crystal structures the metal atoms are coordinated by four water molecules and two pyrazine ligands within slightly distorted octahedra. The pyrazine ligands connect the metal atoms via µ-N,N'-coordination to linear chains which are connected
Yang, Wenbin; Lin, Xiang; Blake, Alexander J; Wilson, Claire; Hubberstey, Peter; Champness, Neil R; Schröder, Martin
2009-12-01
We have synthesized five new metal-organic coordination polymers incorporating the bent ligand H(2)hfipbb [4,4'-(hexafluoroisopropylidene)bis(benzoic acid)] with different transition metal ions and co-ligands via solvothermal reactions to give [Zn(2)(hfipbb)(2)(py)(2)] x DMF (1), [Zn(2)(hfipbb)(2)(4,4'-bipy)(H(2)O)] (2), [Zn(2)(hfipbb)(2)(bpdab)].2DMF (3), [Cd(2)(hfipbb)(2)(DMF)(2)] x 2 DMF (4), and [Co(hfipbb)(dpp)] x MeOH (5) (py = pyridine, 4,4'-bipy = 4,4'-bipyridine, bpdab = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene, dpp = 1,3-di(4-pyridyl)propane). Compound 1 displays a 2-fold 2D-->2D parallel interpenetrated layer network with one-dimensional (1D) helical channels, while 3 exhibits a three-dimensional pillared helical-layer open framework of alpha-Po topology based upon binuclear paddlewheel units. In compounds 2 and 5, binuclear motifs with double carboxylate bridges are linked by hfipbb(2-) ligands into a 1D ribbon, which are further assembled into two-dimensional non-interpenetrated (4,4) layers via bipyridyl co-ligands. However, the different bridging modes of hfipbb(2-) ligands and the different disposition of the coordinated co-ligands around metal ions result in subtle differences in the final architecture. Thus, 2 is based on a binuclear cluster node, double-stranded hfipbb(2-) linkers, and single-stranded 4,4'-bipy linkers, while 5 is based on a binuclear cluster node and hfipbb(2-) and dpp linkers which are both double-stranded. Among these compounds, the Cd(II) complex 4 is possibly the most interesting because it represents a rare example in which metal centers are linked by carboxylate groups into infinite chains further joined together by hfipbb(2-) spacers to form a 2D network with tubular helical channels. All these coordination polymers exhibit low solvent-accessible volumes. Both 3 and 4 retain structural integrity and permanent microporosity upon evacuation of guest molecules, with hydrogen uptakes of 0.57 and 0.78 wt %, respectively, at 20 bar and 77 K. PMID:19943692
One-dimensional Gromov minimal filling problem
Ivanov, Alexandr O; Tuzhilin, Alexey A
2012-05-31
The paper is devoted to a new branch in the theory of one-dimensional variational problems with branching extremals, the investigation of one-dimensional minimal fillings introduced by the authors. On the one hand, this problem is a one-dimensional version of a generalization of Gromov's minimal fillings problem to the case of stratified manifolds. On the other hand, this problem is interesting in itself and also can be considered as a generalization of another classical problem, the Steiner problem on the construction of a shortest network connecting a given set of terminals. Besides the statement of the problem, we discuss several properties of the minimal fillings and state several conjectures. Bibliography: 38 titles.
Ni, Lu-Bin; Zhang, Rong-Hua; Liu, Qiong-Xin; Xia, Wen-Sheng; Wang, Hongxin; Zhou, Zhao-Hui
2009-01-01
Three novel zinc coordination polymers (NH4)n[Zn(Hida)Cl2]n (1), [Zn(ida)(H2O)2]n (2), [Zn(Hida)2]n·4nH2O (3) (H2ida = iminodiacetic acid) and a monomeric complex [Zn(ida)(phen)(H2O)]·2H2O (4) (phen=1,10-phenanthroline) have been synthesized and characterized by X-ray diffraction methods. 1 and 2 form one-dimensional (1-D) chain structures, whereas 3 exhibits a three-dimensional (3-D) diamondoid framework with an open channel. The mononuclear complex 4 is extended into a 3-D supramolecular architecture through hydrogen bonds and ?-? stacking. Interestingly, cyclic nonplanar tetrameric water clusters are observed that encapsulated in the 3-D lattice of 4. Based on 1H and 13C NMR observations, there is obvious coordination of complex 2 in solution, while 1 and 3 decompose into free iminodiacetate ligand. Monomer [Zn(ida)(H2O)3] (5) is considered as a possible discrete species from 2. These coordination polymers can serve as good molecular precursors for zinc oxide. PMID:20161370
NASA Astrophysics Data System (ADS)
Hanifehpour, Younes; Mirtamizdoust, Babak; Hatami, Masoud; Khomami, Bamin; Joo, Sang Woo
2015-07-01
A novel bismuth (III) nano coordination polymer, {[Bi (pcih)(NO3)2]?MeOH}n (1), ("pcih" is the abbreviations of 2-pyridinecarbaldehyde isonicotinoylhydrazoneate) were synthesized by a sonochemical method. The new nano-structure was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray powder diffraction, elemental analyses and IR spectroscopy. Single crystalline material was obtained using a heat gradient applied to a solution of the reagents. Compound 1 was structurally characterized by single crystal X-ray diffraction. The determination of the structure by single crystal X-ray crystallography shows that the complex forms a zig-zag one dimensional polymer in the solid state and the coordination number of BiIII ions is seven, (BiN3O4), with three N-donor and one O-donor atoms from two "pcih" and three O-donors from nitrate anions. It has a hemidirected coordination sphere. The supramolecular features in these complexes are guided and controlled by weak directional intermolecular interactions. The chains interact with each other through ?-? stacking interactions creating a 3D framework. After thermolysis of 1 at 230 °C with oleic acid, pure phase nano-sized bismuth (III) oxide was produced. The morphology and size of the prepared Bi2O3 samples were further observed using SEM.
Bikas, Rahman; Aleshkevych, Pavlo; Hosseini-Monfared, Hassan; Sanchiz, Joaquín; Szymczak, Ritta; Lis, Tadeusz
2015-01-28
A new one dimensional coordination polymer of copper(II), [Cu4(L)2(?2-1,1-OAc)2(?2-1,3-OAc)4]n (1), has been synthesized and characterized by spectroscopic methods and single crystal X-ray analysis [HL = (E)-N'-(phenyl(pyridin-2-yl)methylene)isonicotinhydrazide, OAc = acetate anion]. The coordination polymer contains two kinds of Cu(II) dimers which are connected by two types of acetate (?2-1,1- and ?2-1,3-) bridging groups. The ditopic isonicotinhydrazone ligand coordinates to the Cu1 center through the N2O-donor set and connects to the Cu2 center by a pyridine group of the isonicotine part. The EPR and magnetic susceptibility measurements confirm the existence of two kinds of Cu(II) dimers. The intradimer isotropic exchange was estimated to be +0.80(1) cm(-1) for the ferromagnetic Cu1···Cu1 dimeric unit and -315 (1) cm(-1) for the antiferromagnetic Cu2···Cu2 dimeric unit. PMID:25474021
Resistance of one-dimensional quasicrystals
B. Iochum; L. Raymond; D. Testard
1992-01-01
One-dimensional quasiperiodic systems are often based on an inflation rule giving rise to a recursion formula on the transfer matrices. It is shown in a general setting, that the norm growth of these matrices can be evaluated. A consequence is, for instance, a purely critical regime (namely polynomial bounds in function of the sample size) for the electrical resistance, when
Phonon spectra in one-dimensional quasicrystals
J. M. Luck; D. Petritis
1986-01-01
The propagation of phonons in one-dimensional quasicrystals is investigated. We use the projection method which has been recently proposed to generate almost periodic tilings of the line. We define a natural Laplace operator on these structures, which models phonon (and also tight-binding electron) propagation. The selfsimilarity properties of the spectrum are discussed, as well as some characteristic features of the
The One-Dimensional Heat Equation
NSDL National Science Digital Library
Moore, Lang
Created by Lang Moore for the Connected Curriculum Project, the purpose of this module is to study the symbolic form and graphical representation of the approximate solutions of the one-dimensional heat equation with various boundary and initial conditions. This is one within a much larger set of learning modules hosted by Duke University.
Modeling of Quasi-One-Dimensional
Hod, Oded
will place a special emphasis in theoretical works utilizing density functional theory. We assume Modeling of Quasi-One-Dimensional Carbon Nanostructures with Density Functional Theory Veronica Barone Oded Hod Juan E. Peralta Department of Physics, Central Michigan University, Mount Pleasant
One-Dimensional Oscillator in a Box
ERIC Educational Resources Information Center
Amore, Paolo; Fernandez, Francisco M.
2010-01-01
We discuss a quantum-mechanical model of two particles that interact by means of a harmonic potential and are confined to a one-dimensional box with impenetrable walls. We apply perturbation theory to the cases of different and equal masses and analyse the symmetry of the states in the latter case. We compare the approximate perturbation results…
One-dimensional birefringent photonic crystal laser
Sun Woong Kim; Seung Seok Oh; Jin Ho Park; Eun Ha Choi; Yoon Ho Seo; Guang Sup Cho
2008-01-01
We studied the polarized laser emission from an anisotropic one-dimensional (1D) birefringent photonic crystal (PC) laser. An active medium layer, which consisted of an epoxy resin doped with fluorescent dye, was sandwiched between two anisotropic 1D PC films. It was shown that efficient laser emissions were generated by optical pumping at relatively low lasing thresholds. The wavelengths of the emitted
NASA Astrophysics Data System (ADS)
Fan, Le-Qing; Wu, Ji-Huai; Huang, Yun-Fang
2011-09-01
Two unusual pillared-layer 3 d-4 f Ln-Cu heterometallic coordination polymers, {[ Ln2Cu 5Br 4(IN) 7(H 2O) 6]·H 2O} n ( Ln=Eu ( 1) and Gd ( 2), HIN=isonicotinic acid), have been synthesized under hydrothermal conditions, and characterized by elemental analysis, IR, thermal analysis and single-crystal X-ray diffraction. The structure determination reveals that 1 and 2 are isostructural and feature a novel three-dimensional pillared-layer hetrometallic structure built upon the linkages of one-dimensional (1D) linear Ln-carboxylate chains, zero-dimensional (0D) Ln-carboxylate Ln2(IN) 8 dimers, rare 1D zigzag [Cu 5Br 4] n inorganic chains and IN - pillars. In both 3D structures, there are Ln-carboxylate layers resulted from the connections of 1D Ln-carboxylate chains and 0D Ln2(IN) 8 dimers through O-H⋯O hydrogen bondings. The luminescent properties of 1 have been investigated. The magnetic properties of 1 and 2 have also been studied.
NASA Astrophysics Data System (ADS)
Chao, Tzu-Ling; Yang, Chen-I.
2014-03-01
The preparations and properties of three new homochiral three-dimensional (3D) coordination polymers, [M(D-cam)(pyz)(H2O)2]n (M=Co (1) and Ni (2); D-H2cam=(+) D-camphoric acid; pyz=pyrazine) and [Mn2(D-cam)2(H2O)2] (3), under solvothermal conditions is described. Single-crystal X-ray diffraction analyses revealed that all of compounds are homochiral 3D structure. 1 and 2 are isostructural and crystallize in the trigonal space group P3221, while 3 crystallizes in monoclinic space group P21. The structure of 1 and 2 consists of metal-D-cam helical chains which are pillared with pyrazine ligands into a 3D framework structure and 3 features a 3D homochiral framework involving one-dimensional manganese-carboxylate chains that are aligned parallel to the b axis. Magnetic susceptibility data of all compounds were collected. The findings indicate that ?2-pyrazine dominate weak antiferromagnetic coupling within 1 and 2, while 3 exhibits antiferromagnetic behavior through the carboxylate groups of D-cam ligand.
An exceptional 54-fold interpenetrated coordination polymer with 10(3)-srs network topology.
Wu, Hua; Yang, Jin; Su, Zhong-Min; Batten, Stuart R; Ma, Jian-Fang
2011-08-01
Entanglement is one of the most important features of coordination polymer frameworks and has attracted considerable attention due to its aesthetic and topological interest. Among entangled systems, interpenetrating frameworks represent an intriguing subset; however, there are few examples of materials containing very high levels of interpenetration. In this work a coordination polymer with 10(3)-srs topology, constructed from a star-like tridentate ligand, tri(4-imidazolylphenyl)amine, and Ag(I) ions, has been hydrothermally synthesized. It contains a record 54 interpenetrating networks. PMID:21728370
Liang, Guodong; Ni, Huan; Bao, Suping; Zhu, Fangming; Gao, Haiyang; Wu, Qing; Tang, Ben Zhong
2014-06-01
A class of new amphiphilic nanocapsules entangled with organometallic coordination polymers has been developed for the first time. Poly(2-(N,N-dimethyl amino)ethyl methacrylate)-b-polystyrene capped with ?-cyclodextrin (?-CD) (CD-PDMAEMA-b-PS) is first synthesized using sequent RAFT polymerization of styrene and 2-(N,N-dimethyl amino)ethyl methacrylate with xanthate modified ?-CD as chain transfer agent. The end group of ?-CD is allowed to include 4,4'-bipyridine through host-guest inclusion to yield PDMAEMA-b-PS terminated with an inclusion complex of ?-CD and bipyridine (bpy-PDMAEMA-b-PS), which is then used as surfactant to prepare emulsion droplets in toluene/water mixture. Upon addition of Ni(II), bipyridine coordinates with Ni(II) to form coordination polymers in the periphery of emulsion droplets, affording amphiphilic capsules entangled with organometallic coordination polymers, as confirmed by GPC, (1)H NMR, SEM, TEM, DLS, and so on. The organometallic coordination polymer capsules are capable of encapsulating organic cargoes. Interestingly, encapsulated cargoes can be extracted from the capsules without damaging the capsules. Such capsules are potential candidates for encapsulating and controlled release of organic cargoes. PMID:24828951
Quasi-one-dimensional scattering in a discrete model
NASA Astrophysics Data System (ADS)
Valiente, Manuel; Molmer, Klaus
2012-06-01
We present quasi-one-dimensional scattering of one and two particles with short-range interactions on a discrete lattice model in two dimensions. One of the directions is tightly confined by an arbitrary trapping potential. In the case of two-particle scattering, we will show that more than one confinement-induced resonance appear due to the non-separability of the center-of-mass and relative coordinates on the lattice, which is a necessary ingredient in any experimentally relevant situation.
NASA Astrophysics Data System (ADS)
Huang, Liang; Zhang, Li-Ping; Jin, Lin-Pei
2004-04-01
Reported herein are the hydrothermal synthesis and crystal structures of four lanthanide coordination polymers with nitrilotriacetic acid (H 3NTA) [Ln(NTA)(H 2O)] n (Ln=La, 1; Pr, 2; Nd, 3; Eu, 4). Despite similar syntheses, compounds 1 to 4 show transformation in coordination mode of NTA and coordination number of Ln 3+ duo to lanthanide contraction. The Ln(III) ions in 1 and 2 are nine-coordinated and connected through octadentate bridging ligands (NTA) to form a three-dimensional network. The Ln(III) ions in 3 and 4 are eight-coordinated and bridged by heptadentate bridging ligands (NTA) to form an extended two-dimensional layer structure, which further construct a three-dimensional supramolecular structure via coordination bond and three-centered hydrogen bonding between adjacent layers.
Quasi-one-dimensional scattering in a discrete model
NASA Astrophysics Data System (ADS)
Valiente, Manuel; Mølmer, Klaus
2011-11-01
We study quasi-one-dimensional scattering of one and two particles with short-range interactions on a discrete lattice model in two dimensions. One of the directions is tightly confined by an arbitrary trapping potential. We obtain the collisional properties of these systems both at finite and zero Bloch quasimomenta, considering as well finite sizes and transversal traps that support a continuum of states. This is made straightforward by using the exact ansatz for the quasi-one-dimensional states from the beginning. In the more interesting case of genuine two-particle scattering, we find that more than one confinement-induced resonances appear due to the nonseparability of the center-of-mass and relative coordinates on the lattice. This is done by solving its corresponding Lippmann-Schwinger-like equation. We characterize the effective one-dimensional interaction and compare it with a model that includes only the effect of the dominant, broadest resonance, which amounts to a single-pole approximation for the interaction coupling constant.
Sutar, Papri; Suresh, Venkata M; Maji, Tapas Kumar
2015-06-01
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. PMID:25995095
Vectorlike representation of one-dimensional scattering
L. L. Sanchez-Soto; J. F. Carinena; A. G. Barriuso; J. J. Monzon
2004-11-11
We present a self-contained discussion of the use of the transfer-matrix formalism to study one-dimensional scattering. We elaborate on the geometrical interpretation of this transfer matrix as a conformal mapping on the unit disk. By generalizing to the unit disk the idea of turns, introduced by Hamilton to represent rotations on the sphere, we develop a method to represent transfer matrices by hyperbolic turns, which can be composed by a simple parallelogramlike rule.
Diffraction from quasi-one-dimensional crystals
Vukovic, T.; Milosevic, I.; Damnjanovic, M. [Faculty of Physics, University of Belgrade, P.O. Box 368, 11001 Belgrade (Serbia)
2009-04-15
General expressions of diffraction intensity distribution of quasi-one-dimensional crystals are evaluated within kinematical approximation. In order to gain the generality, diffraction intensity has been derived for each of the fifteen conformation classes. Characteristic features of the diffraction patterns are discussed and it is shown how the symmetry can be fully determined from the diffraction intensity distribution. General results are tabulated and their application is illustrated on the (10,10) molybdenum disulfide nanotube.
One-dimensional s-p superlattice
Wojciech Ganczarek; Michele Modugno; Giulio Pettini; Jakub Zakrzewski
2014-06-23
The physics of one dimensional optical superlattices with resonant $s$-$p$ orbitals is reexamined in the language of appropriate Wannier functions. It is shown that details of the tight binding model realized in different optical potentials crucially depend on the proper determination of Wannier functions. We discuss the properties of a superlattice model which quasi resonantly couples $s$ and $p$ orbitals and show its relation with different tight binding models used in other works.
?-Continuity Properties of One-Dimensional Quasicrystals
David Damanik
1998-01-01
: \\u000a We apply the Jitomirskaya-Last extension of the Gilbert-Pearson theory to discrete one-dimensional Schrödinger operators with\\u000a potentials arising from generalized Fibonacci sequences. We prove for certain rotation numbers that for every value of the\\u000a coupling constant, there exists an ? > 0 such that the corresponding operator has purely ?-continuous spectrum. This result\\u000a follows from uniform upper and lower bounds
Structural and magnetic ordering in the two-dimensional coordination polymer Co(ox)(bpy-d8),
Li, Jing
Structural and magnetic ordering in the two-dimensional coordination polymer Co(ox)(bpy-d8), (ox C susceptibility studies of the two-dimensional coordination polymer Co(ox)(bpy-d8) are presented, where ox C2O22®nite chains that are crosslinked by the bpy ligands. The magnetic susceptibility follows qualitatively a quasi
Yan, Xuzhou; Li, Shijun; Pollock, James Bryant; Cook, Timothy R.; Chen, Jianzhuang; Zhang, Yanyan; Ji, Xiaofan; Yu, Yihua; Huang, Feihe; Stang, Peter J.
2013-01-01
A powerful strategy to obtain complex supramolecular materials is the bottom-up construction of noncovalently bound materials by hierarchical self-assembly. This assembly process involves stepwise, uniform increases to the architectural complexity of a substrate, starting from discrete precursors and growing in dimensionality through controlled reactivity to a final product. Herein, two orthogonal processes are exploited: coordination-driven self-assembly and hydrogen bonding. The former relies on the predictable formation of metal–ligand bonds wherein the directionalities of the rigid precursors used determines the structural outcome. The latter uses 2-ureido-4-pyrimidinone interfaces that are structurally robust by virtue of the quadruple hydrogen bonding that can occur between subunits. By combining these two processes into a single system, it is possible to generate hierarchical materials that preserve the attractive tunability associated with discrete supramolecular coordination complexes. For instance, the synthesis of a one-dimensional chain comprising linked metalla-rhomboids is readily adapted to a 2D cross-linked hexagonal network by simply selecting a different metal acceptor precursor as an assembly component. The specific interactions between subunits, in this case platinum(II)-pyridyl bonds and the quadruple H-bonding of ureidopyrimidinone, are unchanged, establishing a unique strategy to obtain supramolecular polymers with marked topological differences with minimal synthetic redesign. In addition, the structural rigidity imposed by the inclusion of the platinum metallacycles serves to minimize the formation of cyclic oligomers, increasing the efficacy of formation and improving the properties of the resultant materials. Furthermore, this study taps the potential of organoplatinum(II) metallacycles in materials science. PMID:24019475
Syntheses and Study of Some New Coordination Polymers Mn (II) with Semiconductor Properties
I. Rosca; L. Oprea; D. Sutiman; A. Cailean; E. Neagu; M. Vizitiu; D. Sibiescu; G. Apostolescu
2003-01-01
In this paper, the synthesis and the study of some coordination polymers of Mn (II) with ligands derived from acids: dinaphtylphosphinic, dinaphtylthiophosphinic and dinaphtyldithiophosphinic are presented. The synthesis was accomplished by refluxing in organic solvents the reactants: acetylacetonate of Mn (II) and one of the respective phosphinic acids. Studies were performed applying the following methods: chemical analysis, gel chromatography: IR-spectroscopy;
Bernhard, Stefan
Iron(II) and Copper(I) Coordination Polymers: Electrochromic Materials with and without Chiroptical of deterioration over 150 switching cycles. Additionally, in an effort to assemble an electrochromic device with chiroptical properties, the electrochromism of films generated from the enantiomerically pure CTPCT[FeII CTPCT
García-Álvarez, Joaquín; Díez, Josefina; Vidal, Cristian; Vicent, Cristian
2013-06-01
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{?(2)-N,S-(PTA)?NP(?S)(OR)2}]x[SbF6]x (5a and 5b) and [Ag{?(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 ?,?-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. PMID:23675864
Manson, Jamie L; Baldwin, Adora G; Scott, Brian L; Bendix, Jesper; Del Sesto, Rico E; Goddard, Paul A; Kohama, Yoshimitsu; Tran, Hope E; Ghannadzadeh, Saman; Singleton, John; Lancaster, Tom; Möller, Johannes S; Blundell, Stephen J; Pratt, Francis L; Zapf, Vivien S; Kang, Jinhee; Lee, Changhoon; Whangbo, Myung-Hwan; Baines, Christopher
2012-07-16
[Ni(HF(2))(3-Clpy)(4)]BF(4) (py = pyridine) is a simple one-dimensional (1D) coordination polymer composed of compressed NiN(4)F(2) octahedra that form chains with bridging HF(2)(-) ligands. In spite of significant distortion of the HF(2)(-) bridge, a quasi-1D antiferromagnetic (AFM) behavior was observed with J(FHF) = 4.86 K. PMID:22746404
Fan Leqing, E-mail: lqfan@hqu.edu.cn [College of Materials Science and Engineering, Key Laboratory for Functional Materials of Fujian Higher Education, Huaqiao University, Xiamen, Fujian 361021 (China); Wu Jihuai, E-mail: jhwu@hqu.edu.cn [College of Materials Science and Engineering, Key Laboratory for Functional Materials of Fujian Higher Education, Huaqiao University, Xiamen, Fujian 361021 (China); Huang Yunfang [College of Materials Science and Engineering, Key Laboratory for Functional Materials of Fujian Higher Education, Huaqiao University, Xiamen, Fujian 361021 (China)
2011-09-15
Two unusual pillared-layer 3d-4f Ln-Cu heterometallic coordination polymers, {l_brace}[Ln{sub 2}Cu{sub 5}Br{sub 4}(IN){sub 7}(H{sub 2}O){sub 6}].H{sub 2}O{r_brace}{sub n} (Ln=Eu (1) and Gd (2), HIN=isonicotinic acid), have been synthesized under hydrothermal conditions, and characterized by elemental analysis, IR, thermal analysis and single-crystal X-ray diffraction. The structure determination reveals that 1 and 2 are isostructural and feature a novel three-dimensional pillared-layer hetrometallic structure built upon the linkages of one-dimensional (1D) linear Ln-carboxylate chains, zero-dimensional (0D) Ln-carboxylate Ln{sub 2}(IN){sub 8} dimers, rare 1D zigzag [Cu{sub 5}Br{sub 4}]{sub n} inorganic chains and IN{sup -} pillars. In both 3D structures, there are Ln-carboxylate layers resulted from the connections of 1D Ln-carboxylate chains and 0D Ln{sub 2}(IN){sub 8} dimers through O-H...O hydrogen bondings. The luminescent properties of 1 have been investigated. The magnetic properties of 1 and 2 have also been studied. - Graphical abstract: Two unusual pillared-layer Eu (Gd)-Cu heterometallic coordination polymers have been hydrothermally synthesized. The luminescent properties of Eu-Cu compound and magnetic properties of both compounds are investigated. Highlights: > Two unusual 3D pillared-layer Eu (Gd)-Cu heterometallic coordination polymers have been synthesized. > 1D and 0D Ln-carboxylate motifs construct layers by O-H...O hydrogen bondings. > In both the structures, there are rare 1D zigzag Cu/Br inorganic chains. > Luminescent properties of Eu-Cu compound and magnetic properties of both the compounds are investigated.
One dimensional electromagnetic waves on flat surfaces
NASA Astrophysics Data System (ADS)
Horsley, S. A. R.; Hooper, I. R.
2014-10-01
We show that one-dimensional electromagnetic waves can be constrained to propagate along a join between two thin sheets when one surface supports transverse magnetic polarized surface waves and the other supports transverse electric polarized surface waves. We calculate the dispersion relation of these modes and show that they are exceptionally tightly confined to the join, with characteristic decay lengths an order of magnitude smaller than the surface waves supported by each individual surface. We give an example of a metasurface implementation where low frequency instances of such waves may be observed.
One-dimensional hypersonic phononic crystals.
Gomopoulos, N; Maschke, D; Koh, C Y; Thomas, E L; Tremel, W; Butt, H-J; Fytas, G
2010-03-10
We report experimental observation of a normal incidence phononic band gap in one-dimensional periodic (SiO(2)/poly(methyl methacrylate)) multilayer film at gigahertz frequencies using Brillouin spectroscopy. The band gap to midgap ratio of 0.30 occurs for elastic wave propagation along the periodicity direction, whereas for inplane propagation the system displays an effective medium behavior. The phononic properties are well captured by numerical simulations. The porosity in the silica layers presents a structural scaffold for the introduction of secondary active media for potential coupling between phonons and other excitations, such as photons and electrons. PMID:20141118
One-Dimensional Plane Monochromatic Filtration Waves
NASA Astrophysics Data System (ADS)
Filippov, A. I.; Akhmetova, O. V.
2015-03-01
Equations and relations to describe one-dimensional plane monochromatic fi ltration waves in a homogeneous isotropic porous medium have been obtained. To this end, use was made of the equation of motion of a liquid phase with account of frictional forces, which in the case of steady-state fi ltration with parallel streamlines agrees with Darcy's fi ltration law for an anisotropic medium. The equations of motion and continuity reduced to an equation of telegraphy enabled us to construct relations for the wave number, the absorption and attenuation coefficients, and the velocity of filtration waves.
Fan, Le-Qing, E-mail: lqfan@hqu.edu.c [Institute of Materials Physical Chemistry, and the Key Laboratory for Functional Materials of Fujian Higher Education, Huaqiao University, Quanzhou, Fujian 362021 (China); Chen, Yuan [Institute of Materials Physical Chemistry, and the Key Laboratory for Functional Materials of Fujian Higher Education, Huaqiao University, Quanzhou, Fujian 362021 (China); Wu, Ji-Huai, E-mail: jhwu@hqu.edu.c [Institute of Materials Physical Chemistry, and the Key Laboratory for Functional Materials of Fujian Higher Education, Huaqiao University, Quanzhou, Fujian 362021 (China); Huang, Yun-Fang [Institute of Materials Physical Chemistry, and the Key Laboratory for Functional Materials of Fujian Higher Education, Huaqiao University, Quanzhou, Fujian 362021 (China)
2011-04-15
Two new 4d-4f Ln-Ag heterometallic coordination polymers, {l_brace}[Ln{sub 3}Ag{sub 5}(IN){sub 10}(H{sub 2}O){sub 7}].4(ClO{sub 4}).4(H{sub 2}O){r_brace}{sub n} (Ln=Eu (1) and Sm (2), HIN=isonicotinic acid), have been synthesized under hydrothermal conditions by reactions of Ln{sub 2}O{sub 3}, AgNO{sub 3}, HIN and HClO{sub 4}, and characterized by elemental analysis, IR, thermal analysis and single-crystal X-ray diffraction. It is proved that HClO{sub 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){sub 2} units. The 2D layers are further interlinked through Ag...Ag and Ag...O(ClO{sub 4}{sup -}) multiple weak interactions, which form a rare Ag-ClO{sub 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. -- Graphical abstract: Two new anion-templated 2D 4d-4f Ln-Ag heterometallic coordination polymers based on novel lanthanide-carboxylate chains and pillared Ag(IN){sub 2} units, {l_brace}[Ln{sub 3}Ag{sub 5}(IN){sub 10}(H{sub 2}O){sub 7}].4(ClO{sub 4}).4(H{sub 2}O){r_brace}{sub n} (Ln=Eu (1) and Sm (2), HIN=isonicotinic acid), have been hydrothermally synthesized and structurally characterized. 1 and 2 exhibit good luminescent properties. Display Omitted Research highlights: > Two 2D Eu (Sm)-Ag coordination polymers templated by perchlorate anion have been synthesized. > Polymers consist of novel 1D lanthanide-carboxylate chains. > In both structures, there are rare Ag...Ag and Ag...O(ClO{sub 4}{sup -}) multiple weak interactions. > Both compounds exhibit good luminescent properties.
One-dimensional coinless quantum walks
NASA Astrophysics Data System (ADS)
Portugal, Renato; Boettcher, Stefan; Falkner, Stefan
2015-05-01
A coinless, discrete-time quantum walk possesses a Hilbert space whose dimension is smaller compared to the widely studied coined walk. Coined walks require the direct product of the site basis with the coin space; coinless walks operate purely in the site basis, which is clearly minimal. These coinless quantum walks have received considerable attention recently because they have evolution operators that can be obtained by a graphical method based on lattice tessellations and they have been shown to be as efficient as the best known coined walks when used as a quantum search algorithm. We argue that both formulations in their most general form are equivalent. In particular, we demonstrate how to transform the one-dimensional version of the coinless quantum walk into an equivalent extended coined version for a specific family of evolution operators. We present some of its basic, asymptotic features for the one-dimensional lattice with some examples of tessellations, and analyze the mixing time and limiting probability distributions on cycles.
Gu, Jin-Zhong; Wu, Jiang; Lv, Dong-Yu; Tang, Yu; Zhu, Kongyang; Wu, Jincai
2013-04-14
Twelve lanthanide coordination polymers associated with the organic ligand 5-(2?-carboxylphenyl) nicotinic acid (H2cpna): {[Ln(Hcpna)(cpna)(phen)]·H2O}n (Ln = Sm (1), Tb (2), Ho (3), phen = 1,10-phenanthroline), {[Sm(Hcpna)(cpna)(phen)]·2H2O}n (4), {[Ln2(cpna)3(H2O)3]·4H2O}n (Ln = Y (5), Tb(6), Dy (7), Ho (8)), [Lu2(cpna)3(H2O)2]n (9), {[Y2(cpna)3(phen)2(H2O)]·H2O}n (10), and [Ln(cpna)(phen)(NO3)]n (Ln = Tm (11), Lu (12)) have been prepared by hydrothermal methods and structurally characterized. The structure analyses reveal that complexes 1–3 are isostructural and possess unique three-dimensional (3D) frameworks based on the dodecanuclear Sm/Tb/Ho macrocycles. Complex 4 exhibits a one-dimensional (1D) wheel-chain structure, which further builds three-dimensional (3D) supramolecular architecture via O–HN hydrogen-bonding interactions. Complexes 5–8 are also isostructural and display three-dimensional (3D) open frameworks, which possess two types of channels along the a- and b-axis, respectively. Complexes 9 and 10 feature three-dimensional (3D) frameworks and are created from tetranuclear and dinuclear units, respectively. Complexes 11 and 12 are isostructural and demonstrate one-dimensional (1D) double chain structures, which further build three-dimensional (3D) supramolecular architecture via C–H···O hydrogen-bonding. The results show that the pH value of the reaction system, anion, auxiliary ligand and lanthanide contraction play a significant role in determining the structures of the complexes. In addition, the results of luminescent measurements for compounds 2 and 6 in the solid state at room temperature indicate that the different types of structures have a dissimilar influence on their characteristic luminescence. The magnetic properties of compounds 1, 3, 4, 7 and 11 have been investigated. Furthermore, thermal stabilities for 1–12 and the dehydration/hydration properties of compound 6 have also been studied. PMID:23364602
One-dimensional frequency-based spectroscopy.
Cygan, Agata; Wcis?o, Piotr; Wójtewicz, Szymon; Mas?owski, Piotr; Hodges, Joseph T; Ciury?o, Roman; Lisak, Daniel
2015-06-01
Recent developments in optical metrology have tremendously improved the precision and accuracy of the horizontal (frequency) axis in measured spectra. However, the vertical (typically absorbance) axis is usually based on intensity measurements that are subject to instrumental errors which limit the spectrum accuracy. Here we report a one-dimensional spectroscopy that uses only the measured frequencies of high-finesse cavity modes to provide complete information about the dispersive properties of the spectrum. Because this technique depends solely on the measurement of frequencies or their differences, it is insensitive to systematic errors in the detection of light intensity and has the potential to become the most accurate of all absorptive and dispersive spectroscopic methods. The experimental results are compared to measurements by two other high-precision cavity-enhanced spectroscopy methods. We expect that the proposed technique will have significant impact in fields such as fundamental physics, gas metrology and environmental remote sensing. PMID:26072808
Electronic Correlations in One-Dimensional Superlattices
NASA Astrophysics Data System (ADS)
Paiva, Thereza; Dos Santos, Raimundo R.
1996-02-01
We consider fermions on a one-dimensional superlattice, represented by a repeated pattern of repulsive (i.e., positive Hubbard U) and free (i.e., U = 0) sites. Lanczos diagonalization of chains up to 12 sites at half filling shows that some patterns give rise to a weak form of frustration, sufficient to wipe out the spin-density-wave (SDW) correlations present in the otherwise homogeneous system. On the other hand, SDW correlations appear for some patterns above half filling, a feature absent in the homogeneous case. Below half filling, the local-moment maxima are displaced from the repulsive to the free sites. The peak in the magnetic structure factor is also shifted from q = ?, for the alternating configuration when ? = 1/3 and 5/3.
Three one-dimensional structural heating programs
NASA Technical Reports Server (NTRS)
Wing, L. D.
1978-01-01
Two computer programs for calculating profiles in a ten-element structure consisting of up to ten materials are presented, along with a third program for calculating the mean temperature for a payload container placed in an orbiting vehicle cargo bay. The three programs are related by the sharing of a common analytical technique; the energy balance is based upon one-dimensional heat transfer. The first program, NQLDW112, assumes a non-ablating surface. NQLDW117 is very similar but allows the outermost element to ablate. NQLDW040 calculates an average temperature profile through an idealized model of the real payload cannister and contents in the cargo bay of an orbiting vehicle.
Jin Jing; Han Xiao; Meng Qin; Li Dan; Chi Yuxian [School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029 (China); Niu Shuyun, E-mail: syniu@sohu.com [School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029 (China)
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 complexes 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.
Lee, Jai Young; Kim, Hyun Jee; Jung, Jong Hwa; Sim, Wonbo; Lee, Shim Sung
2008-10-22
Solvato-PL switching and shrinking-and-opening process: we present two CuI coordination polymers of calix[4]-bis-monothiacrown (L) obtained in the absence (1) and presence (2) of KI. The structures show not only very unusual CuI-based network arrangements but also unique reversible photolunimescence switching behavior induced by removal of coordinated solvent. Furthermore, upon inclusion of K+ ions the crown ring shrinks leading to "opening" of opposite aromatic rings in the host calixarene unit, rare behavior for this class of compound. PMID:18817393
Virtual high throughput screening confirmed experimentally: porous coordination polymer hydration.
Low, John J; Benin, Annabelle I; Jakubczak, Paulina; Abrahamian, Jennifer F; Faheem, Syed A; Willis, Richard R
2009-11-01
Hydrothermal stability is a pertinent issue to address for many industrial applications where percent levels of water can be present at temperatures ranging from subambient to several hundred degrees. Our objective is to understand relative stabilities of MOF materials through experimental testing combined with molecular modeling. This will enable the ultimate design of materials with improved hydrothermal stability, while maintaining the properties of interest. The tools that we have employed for these studies include quantum mechanical calculations based upon cluster models and combinatorial steaming methods whereby a steam stability map was formulated according to the relative stability of different materials. The experimental steaming method allows for high throughput screening of materials stability over a broad range of steam levels as well as in-depth investigation of structural transformations under more highly resolved conditions, while the cluster model presented here yields the correct trends in hydrothermal stability. Good agreement was observed between predicted relative stabilities of materials by molecular modeling and experimental results. Fundamental information from these studies has provided insight into how metal composition and coordination, chemical functionality of organic linker, framework dimensionality, and interpenetration affect the relative stabilities of PCP materials. This work suggests that the strength of the bond between the metal oxide cluster and the bridging linker is important in determining the hydrothermal stability of the PCP. Although the flexibility of the framework plays a role, it is not as important as the metal-linker bond strength. This demonstration of alignment between experimental and calculated observations has proven the validity of the method, and the insight derived herein insight facilitates direction in designing ideal MOF materials with improved hydrothermal stability for desired applications. PMID:19810730
NASA Astrophysics Data System (ADS)
Everitt, D. T.; Coope, T. S.; Trask, R. S.; Wass, D. F.; Bond, I. P.
2015-05-01
A silver–olefin based coordination polymer was prepared in a simple, one step process to act as an initiator to facilitate the ring-opening polymerization of epoxides. Thermal analysis found the complex to be capable of curing a range of commercially available epoxy resins used in the manufacture of conventional composite materials. Curing of the oligomeric diglycidyl ether bisphenol A resin, Epon 828, in combination with a non-toxic solvent, ethyl phenylacetate, was studied by differential scanning calorimetry. The mechanical characterization of the resultant cured polymers was conducted by single lap shear tests. Tapered double cantilever beam (TDCB) test specimens containing 2.5 pph of silver–olefin initiator, both with and without embedded microcapsules, were analyzed for their healing performance. Healing efficiency values were found to be strongly dependent on the applied healing temperature. A mean recovery of 74% fracture load was found in TDCB samples after being healed at 70 °C for 48 h.
SUSY-inspired one-dimensional transformation optics
Mohammad-Ali Miri; Matthias Heinrich; Demetrios N. Christodoulides
2014-08-04
Transformation optics aims to identify artificial materials and structures with desired electromagnetic properties by means of pertinent coordinate transformations. In general, such schemes are meant to appropriately tailor the constitutive parameters of metamaterials in order to control the trajectory of light in two and three dimensions. Here we introduce a new class of one-dimensional optical transformations that exploits the mathematical framework of supersymmetry (SUSY). This systematic approach can be utilized to synthesize photonic configurations with identical reflection and transmission characteristics, down to the phase, for all incident angles, thus rendering them perfectly indistinguishable to an external observer. Along these lines, low-contrast dielectric arrangements can be designed to fully mimic the behavior of a given high-contrast structure that would have been otherwise beyond the reach of available materials and existing fabrication techniques. Similar strategies can also be adopted to replace negative-permittivity domains, thus averting unwanted optical losses.
Bu, Fan-Xing; Xu, Li; Zhang, Wei; Jin, Chuan-Yin; Qi, Rui-Juan; Huang, Rong; Jiang, Ji-Sen
2015-04-11
We have developed one versatile spatially confined self-assembly strategy to integrate cyanometallate-based coordination polymers with functional metal oxides into well-defined core@shell heterostructures. The structure, composition, size and morphology of the heterostructures could be facilely controlled. The obtained Fe3O4@Prussian blue heterostructure was evaluated as an appealing multifunctional thermal ablation agent exhibiting response to both magnetic field and light irradiation. PMID:25753227
Jeon, Hyung Joon; Matsuda, Ryotaro; Kanoo, Prakash; Kajiro, Hiroshi; Li, Liangchun; Sato, Hiroshi; Zheng, Yongtai; Kitagawa, Susumu
2014-09-25
A perfluorobutyl-functionalized two-dimensional porous coordination polymer (PCP), {[Cu(bpbtp)(L)(DMF)]·(DMF)}n (H2bpbtp = 2,5-bis(perfluorobutyl)terephthalic acid, L = 2,5-bis(perfluorobutyl)-1,4-bis(4-pyridyl)benzene, DMF = N,N-dimethylformamide) has been synthesized and structurally characterized. The pore surface of the PCP is decorated with pendant perfluorobutyl groups which fabricate a densely fluorinated nanospace resulting in unique gas sorption properties. PMID:25089888
Synthesis, crystal structure and fluorescence of a new triazolated-bridged 2-D coordination polymer
Bing Liu; Zhi-Qiang Zhou; Xiu-Cheng Zhang; Xian-You Zhang
2007-01-01
In the 2-D coordination polymer [Zn(L)Cl]n (HL=3-amino-1H-1,2,4-triazole) synthesized by diffusion method, L? ligands link Zn2+ to form 6- and 16-membered rings. The interconnection of the two kinds of rings results in a 2-D network, which features a (4,82) topological network. Hydrogen bonds connect the neighboring plane-symmetry layers into a 3-D framework. The fluorescence with emission at 416nm is assigned to
NASA Astrophysics Data System (ADS)
Diab, M. A.; El-Sonbati, A. Z.; Mohamed, R. H.
2010-11-01
Novel polymer complexes of copper(II), palladium(II), platinum(II) and cadmium(II) containing homopolymer [4-acrylamido benzene sulphonyl guanidine; (HL)] and various anions (SO 42-, CH 3COO -, NO 3-, Br - or Cl -) have been designed and carried out. Their structures were investigated by elemental analyses, spectral (IR, UV-vis, 1H NMR and ESR) and magnetic moments. The modes of interactions between the ligand and the metals were discussed, where oxygen (of O dbnd S dbnd O group) and nitrogen atom [of imino nitrogen (NH/N) of the guanidine group] are involved in chelation. The homopolymer shows two types of coordination behaviour. In mononuclear polymer complexes 4 and 6- 10, it acts as a neutral bidentate ligand chelated through the NH and O atoms, whereas in the polymer complexes 1- 3, 5 and 11, monobasic bidentate ligand is coordinated through the -N and -O atoms. The poly-chelates are of 1:1/1:2 (metal-homopolymer) stoichiometry and exhibit four coordination. On the basis of electronic spectral data and magnetic susceptibility measurement square planar geometry has been proposed. The ESR spectral data provided information about their structure on the basis Hamiltonian parameters and degree of covalency. From the electron paramagnetic resonance and spectral data, the orbital reduction factors were calculated.
Bernhard, Stefan; Goldsmith, Jonas I; Takada, Kazutake; Abruña, Héctor D
2003-07-14
The electrochemical and optical properties of films prepared from two different Fe(II) coordination polymers (TPT[Fe(II)TPT](n)(PF(6))(2)(n) (TPT = terpyridine-phenyl-terpyridine) and CTPCT[Fe(II)CTPCT](n)(PF(6))(2)(n) (CTPCT = chiral terpyridine-phenyl-chiral terpyridine)) and a coordination polymer based on Cu(I) metal centers (PDP[Cu(I)PDP](n)(BF(4))(n)) (PDP = phenanthroline-dodecane-phenanthroline) have been studied. The oxidation of a PDP[Cu(I)PDP](n)(BF(4))(n) film coated on an indium-tin oxide (ITO) electrode by stepping the potential from 0.0 to +1.4 V vs Ag/AgCl led not only to the complete bleaching of the absorption in the visible region of the spectrum within 5 min but also to a redox-induced dissociation and dissolution of the polymer. The reverse reaction of binding and reassembling the polymer at the electrode surface, upon stepping the potential back to 0.0 V, occurred with a rate which was at least 1 order of a magnitude slower. In contrast, the bis(2,2':6',2' '-terpyridine)iron(II)-based redox polymers TPT[Fe(II)TPT](n)(PF(6))(2)(n) and CTPCT[Fe(II)CTPCT](n)(PF(6))(2)(n), during similar spectroelectrochemical experiments, not only exhibited a dramatically enhanced switching rate but also displayed symmetric switching kinetics. The films did not show signs of deterioration over 150 switching cycles. Additionally, in an effort to assemble an electrochromic device with chiroptical properties, the electrochromism of films generated from the enantiomerically pure CTPCT[Fe(II)CTPCT](n)(PF(6))(2)(n) polymer was studied through circular dichroism. PMID:12844311
Exciton quasicondensation in one-dimensional systems
NASA Astrophysics Data System (ADS)
Werman, Yochai; Berg, Erez
2015-06-01
Two Luttinger liquids, with an equal density and opposite sign of charge carriers, may exhibit enhanced excitonic correlations. We term such a system an exciton quasicondensate, with a possible realization being two parallel oppositely doped quantum wires, coupled by repulsive Coulomb interactions. We show that this quasiexciton condensate can be stabilized in an extended range of parameters, in both spinless and spinful systems. We calculate the interwire tunneling current-voltage characteristic, and find that a negative differential conductance is a signature of excitonic correlations. For spinful electrons, the excitonic regime is shown to be distinct from the usual quasi-long-range ordered Wigner crystal phase characterized by power-law density wave correlations. The two phases can be clearly distinguished through their interwire tunneling current-voltage characteristics. In the quasiexciton condensate regime the tunneling conductivity diverges at low temperatures and voltages, whereas in the Wigner crystal it is strongly suppressed. Both the Wigner crystal and the excitonic regime are characterized by a divergent Coulomb drag at low temperature. Finally, metallic carbon nanotubes are considered as a special case of such a one-dimensional setup, and it is shown that exciton condensation is favorable due to the additional valley degree of freedom.
One-dimensional model of inertial pumping.
Kornilovitch, Pavel E; Govyadinov, Alexander N; Markel, David P; Torniainen, Erik D
2013-02-01
A one-dimensional model of inertial pumping is introduced and solved. The pump is driven by a high-pressure vapor bubble generated by a microheater positioned asymmetrically in a microchannel. The bubble is approximated as a short-term impulse delivered to the two fluidic columns inside the channel. Fluid dynamics is described by a Newton-like equation with a variable mass, but without the mass derivative term. Because of smaller inertia, the short column refills the channel faster and accumulates a larger mechanical momentum. After bubble collapse the total fluid momentum is nonzero, resulting in a net flow. Two different versions of the model are analyzed in detail, analytically and numerically. In the symmetrical model, the pressure at the channel-reservoir connection plane is assumed constant, whereas in the asymmetrical model it is reduced by a Bernoulli term. For low and intermediate vapor bubble pressures, both models predict the existence of an optimal microheater location. The predicted net flow in the asymmetrical model is smaller by a factor of about 2. For unphysically large vapor pressures, the asymmetrical model predicts saturation of the effect, while in the symmetrical model net flow increases indefinitely. Pumping is reduced by nonzero viscosity, but to a different degree depending on the microheater location. PMID:23496615
Global solutions to one-dimensional shallow water magnetohydrodynamic
Global solutions to one-dimensional shallow water magnetohydrodynamic equations Y.-G. Lu Department study the Cauchy problem for the one-dimensional shallow water magnetohydrodynamic equations. The main or for the Chaplygin gas. 1 Introduction The following one-dimensional, magnetohydrodynamic shallow water equations
Hierarchical effect behind the supramolecular chirality of silver(I)-cysteine coordination polymers.
Randazzo, Rosalba; Di Mauro, Alessandro; D'Urso, Alessandro; Messina, Gabriele C; Compagnini, Giuseppe; Villari, Valentina; Micali, Norberto; Purrello, Roberto; Fragalà, Maria Elena
2015-04-01
Cysteine is a sulfur-containing amino acid that easily coordinates to soft metal ions and grafts to noble metal surfaces. Recently, chiroptical activity of Ag(+)/cysteine coordination polymers has been widely studied, while, on the other hand, the appearance of a plasmon-enhanced circular dichroic signal (PECD) at the plasmonic spectral region (? > 400 nm) has been observed for AgNPs capped with chiral sulfur-containing amino acids. These two events are both potentially exploited for sensing applications. However, the presence of Ag(+) ions in AgNP colloidal solution deals with the competition of cysteine grafting at the metal NP surface and/or metal ion coordination. Herein we demonstrate that the chiroptical activity observed by adding cysteine to AgNP colloids prepared by pulsed laser ablation in liquids (PLAL) is mainly related to the formation of CD-active Ag(+)/cysteine supramolecular polymers. The strict correlation between supramolecular chirality and hierarchical effects, driven by different chemical environments experienced by cysteine when different titration modalities are used, is pivotal to validate cysteine as a fast and reliable probe to characterize the surface oxidation of AgNPs prepared by pulsed laser ablation in liquids by varying the laser wavelengths. PMID:25781213
NASA Astrophysics Data System (ADS)
Yutkin, M. P.; Dybtsev, D. N.; Fedin, Vladimir P.
2011-11-01
The review concerns the state of the art in and prospects for the development of chemistry of a new class of porous compounds, homochiral metal-organic coordination polymers. Main approaches to the synthesis and structure determination of such systems by X-ray diffraction analysis, as well as stability of metal-organic frameworks and supramolecular chemistry of host-guest inclusion compounds are considered. Prospects for practical application of these compounds first of all for enantioselective resolution and catalysis are discussed. The bibliography includes 175 references. Dedicated to Academician O M Nefedov on the occasion of his 80th birthday.
Crystal-chemical role of malonate ions in the structure of coordination polymers
NASA Astrophysics Data System (ADS)
Serezhkin, V. N.; Medvedkov, Ya. A.; Serezhkina, L. B.; Pushkin, D. V.
2015-06-01
In the crystal structures of the malonate-containing compounds of d- or f-metals, the C3H2O{4/2-} anions were found to exhibit 17 topologically different types of coordination to the metal atoms A, playing the role of mono-, bi-, tri-, or tetradentate ligands and forming one to seven O-A bonds. The C-C-C bond angle in the malonate ions changed from 103° to 126° and depended linearly on the dihedral angle (?COO) between the planes of the two carboxyl groups of the anion. At ?COO < 60°, the malonate ions in the crystal structures always form six-membered metallocycles with d- or f-metal atoms, while at ?COO > 67°, they can form only four-membered metallocycles. The factors that influence the conformation of malonate ions in the structures of coordination polymers were discussed.
NASA Astrophysics Data System (ADS)
Jin, Jing; Gong, Yuanyuan; Li, Lei; Han, Xiao; Meng, Qin; Liu, Yonghua; Niu, Shuyun
2015-02-01
Four Co(II) coordination polymers, [Co(suc)]n1, [Co(pdc)]n2, {[Co7(suc)4(OH)6(H2O)3] · 8H2O}n3, {[Co(bdc)(phen)(H2O)] · H2O}n4 (H2suc = succinic acid, H2pdc = pyridine-3,4-dicarboxylic acid, H2bdc = 1,2-benzenedicarboxylic acid, phen = 1,10-phenanthroline) were hydrothermally synthesized and characterized by X-ray single-crystal diffraction, surface photovoltage spectroscopy (SPS), electrical conductivity, thermogravimetric analysis (TG), ultraviolet visible and near-infrared absorption spectrum (UV-Vis-NIR), infrared spectrum (IR), and elemental analysis. The structural analyses indicate that the coordination numbers of the Co(II) ions are 4, 5, 6 and 6 for the polymers 1-4, respectively. And polymers 1 and 2 exhibit 3D structure formed by suc2- and pdc2- anions bridging Co(II) ions, respectively. Polymer 3 exhibits a 2D structure with suc2- anions bridging seven-nuclear [Co7(OH)6(H2O)3]3- unit and polymer 4 is a 1D structure bridged by bdc2- anions. The surface photoelectric properties of the cobalt polymers were mainly studied by SPS. The results of SPS reveal that all polymers possess certain photoelectric conversion property in the range of 300-800 nm. The influences of the structure, coordination micro-environment of central metal ion and structural dimensionality on response bands of SPS were discussed.
Thermal and Electrical Transport Study of One Dimensional Nanomaterials
Yin, Liang
2013-07-13
THERMAL AND ELECTRICAL TRANSPORT STUDY OF ONE DIMENSIONAL NANOMATERIALS A Dissertation by LIANG YIN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... materials, especially one-dimensional nanomaterials, are being actively studied for thermoelectric application. For instance, the three common one-dimensional (1D) nanostructures (carbon nanotubes10, 34-36, silicon / silicon germanium alloy nanowires11...
Montes, Victor A; Zyryanov, Grigory V; Danilov, Evgeny; Agarwal, Neeraj; Palacios, Manuel A; Anzenbacher, Pavel
2009-02-11
Understanding the excited-state dynamics in conjugated systems can lead to their better utilization in optical sensors, organic photovoltaics (OPVs), and organic light-emitting diodes (OLEDs). We present the synthesis of self-assembled coordination polymers comprising two types of fluorescent moieties: discrete fluorene oligomers of a well-defined length (n = 1-9) connected via aluminum(III) bis(8-quinolinolate)acetylacetone joints. Due to their well-defined structure, these materials allowed for a detailed study of energy migration processes within the materials. Thus, femtosecond transient spectroscopy was used to study the ultrafast energy transfer from the oligofluorene to the quinolinolate moieties, which was found to proceed at a rate of 10(11) s(-1). The experimental results were found to be in agreement with the behavior predicted according to the Beljonne's improved Forster model of energy transfer. In addition, the solid-state and semiconductor properties of these coordination polymers allowed for the fabrication of OLEDs. Preliminary experiments with simple two- and three-layer devices fabricated by spin-coating yield bright yellow electroluminescence with maximum brightness of 6000 cd/m(2), with a turn-on voltage of approximately 6 V and a maximum external quantum efficiency of up to 1.2%, suggesting their potential for use in PLED applications. PMID:19146416
A family of lanthanide-based coordination polymers with boronic Acid as ligand.
Fan, Xiao; Freslon, Stéphane; Daiguebonne, Carole; Pollès, Laurent Le; Calvez, Guillaume; Bernot, Kevin; Yi, Xiaohui; Huang, Gang; Guillou, Olivier
2015-06-01
Reactions in water between the sodium salt of 4-carboxyphenylboronic acid (Hcpb) and lanthanide ions (Pr-Nd, Sm-Lu, and Y) led to a family of lanthanide-based coordination polymers with general chemical formula {[Ln(cpbOH)(H2O)2](cpb)}?. Structural characterizations were ensured by single-crystal X-ray diffraction and solid-state NMR spectroscopy ((11)B, (13)C, and (89)Y). This family of compounds constitutes the first example of lanthanide-based coordination polymers involving 4-carboxyphenylboronic acid as ligand. To evaluate their potential usefulness, luminescent and magnetic properties of some of the compounds that constitute this family were explored. From a magnetic point of view, the Yb(III) compound is the more promising. On the other hand, upon UV irradiation (?exc = 303 nm) ligand phosphorescence is quite intense and offers a sizable blue component to emission spectra. This is quite unusual and can constitute an asset as far as white emission is targeted. Moreover, luminescence properties of these compounds are highly temperature-dependent, and some of them seem promising as molecular thermometers. PMID:25974836
Zheng, Kai; Lou, Kai-Li; Zeng, Cheng-Hui; Li, Sha-Sha; Nie, Zhi-Wen; Zhong, Shengliang
2015-07-01
A new hybrid membrane was prepared by a facile method based on a highly luminescent lanthanide coordination polymer and agarose. The soft membrane was characterized by FT-IR, PXRD, SEM and luminescence. It is found that the soft membrane is a highly selective and sensitive sensor, among 19 metal ion solutions of Fe(3+) , Mg(2+) , Li(+) , Ca(2+) , Zn(2+) , Cu(2+) , Ba(2+) , Mn(2+) , Ru(3+) , Cr(3+) , Ag(+) , Sr(2+) , Cd(2+) , Na(+) , Ni(2+) , Pb(2+) , Fe(2+) , Hg(2+) and Ca(2+) , only Fe(3+) quench the luminescence. The sensing results can be distinguished by the naked eye in daylight or by irradiation of a portable UV light at the scene. Mechanism studies reveal the sensing is due to the decomposition of the coordination polymer 1 which induced by slow permeation of Fe(3+) . Further studies found anions of BO3-, CO32-, H2PO4-, Br(-) , Cl(-) , ClO4-, H2PO4-, I(-) , IO3- and NO3- will not quench the luminescence of the hybrid membrane, which imply that other anions in water would not disturb the detection result. PMID:25892403
Multi-Symplectic Lagrangian, One-Dimensional Gas Dynamics
G. M. Webb
2015-02-12
The equations of Lagrangian, ideal, one-dimensional (1D), compressible gas dynamics are written in a multi-symplectic form using the Lagrangian mass coordinate $m$ and time $t$ as independent variables, and in which the Eulerian position of the fluid element $x=x(m,t)$ is one of the dependent variables. This approach differs from the Eulerian, multi-symplectic approach using Clebsch variables. Lagrangian constraints are used to specify equations for $x_m$, $x_t$ and $S_t$ consistent with the Lagrangian map, where $S$ is the entropy of the gas. We require $S_t=0$ corresponding to advection of the entropy $S$ with the flow. We show that the Lagrangian Hamiltonian equations are related to the de Donder-Weyl multi-momentum formulation. The pullback conservation laws and the symplecticity conservation laws are discussed. The pullback conservation laws correspond to invariance of the action with respect to translations in time (energy conservation) and translations in $m$ in Noether's theorem. The conservation law due to $m$-translation invariance gives rise to a novel nonlocal conservation law involving the Clebsch variable $r$ used to impose $\\partial S(m,t)/\\partial t=0$. Translation invariance with respect to $x$ in Noether's theorem is associated with momentum conservation. We obtain the Cartan-Poincar\\'e form for the system, and use it to obtain a closed ideal of two-forms representing the equation system.
Multi-symplectic, Lagrangian, one-dimensional gas dynamics
NASA Astrophysics Data System (ADS)
Webb, G. M.
2015-05-01
The equations of Lagrangian, ideal, one-dimensional, compressible gas dynamics are written in a multi-symplectic form using the Lagrangian mass coordinate m and time t as independent variables, and in which the Eulerian position of the fluid element x = x(m, t) is one of the dependent variables. This approach differs from the Eulerian, multi-symplectic approach using Clebsch variables. Lagrangian constraints are used to specify equations for xm, xt, and St consistent with the Lagrangian map, where S is the entropy of the gas. We require St = 0 corresponding to advection of the entropy S with the flow. We show that the Lagrangian Hamiltonian equations are related to the de Donder-Weyl multi-momentum formulation. The pullback conservation laws and the symplecticity conservation laws are discussed. The pullback conservation laws correspond to invariance of the action with respect to translations in time (energy conservation) and translations in m in Noether's theorem. The conservation law due to m-translation invariance gives rise to a novel nonlocal conservation law involving the Clebsch variable r used to impose ?S(m, t)/?t = 0. Translation invariance with respect to x in Noether's theorem is associated with momentum conservation. We obtain the Cartan-Poincaré form for the system, and use it to obtain a closed ideal of two-forms representing the equation system.
Localized cell stimulation by nitric oxide using a photoactive porous coordination polymer platform.
Diring, Stéphane; Wang, Dan Ohtan; Kim, Chiwon; Kondo, Mio; Chen, Yong; Kitagawa, Susumu; Kamei, Ken-ichiro; Furukawa, Shuhei
2013-01-01
Functional cellular substrates for localized cell stimulation by small molecules provide an opportunity to control and monitor cell signalling networks chemically in time and space. However, despite improvements in the controlled delivery of bioactive compounds, the precise localization of gaseous biomolecules at the single-cell level remains challenging. Here we target nitric oxide, a crucial signalling molecule with site-specific and concentration-dependent activities, and we report a synthetic strategy for developing spatiotemporally controllable nitric oxide-releasing platforms based on photoactive porous coordination polymers. By organizing molecules with poor reactivity into polymer structures, we observe increased photoreactivity and adjustable release using light irradiation. We embed photoactive polymer crystals in a biocompatible matrix and achieve precisely controlled nitric oxide delivery at the cellular level via localized two-photon laser activation. The biological relevance of the exogenous nitric oxide produced by this strategy is evidenced by an intracellular change in calcium concentration, mediated by nitric oxide-responsive plasma membrane channel proteins. PMID:24158008
Localized cell stimulation by nitric oxide using a photoactive porous coordination polymer platform
Diring, Stéphane; Wang, Dan Ohtan; Kim, Chiwon; Kondo, Mio; Chen, Yong; Kitagawa, Susumu; Kamei, Ken-ichiro; Furukawa, Shuhei
2013-01-01
Functional cellular substrates for localized cell stimulation by small molecules provide an opportunity to control and monitor cell signalling networks chemically in time and space. However, despite improvements in the controlled delivery of bioactive compounds, the precise localization of gaseous biomolecules at the single-cell level remains challenging. Here we target nitric oxide, a crucial signalling molecule with site-specific and concentration-dependent activities, and we report a synthetic strategy for developing spatiotemporally controllable nitric oxide-releasing platforms based on photoactive porous coordination polymers. By organizing molecules with poor reactivity into polymer structures, we observe increased photoreactivity and adjustable release using light irradiation. We embed photoactive polymer crystals in a biocompatible matrix and achieve precisely controlled nitric oxide delivery at the cellular level via localized two-photon laser activation. The biological relevance of the exogenous nitric oxide produced by this strategy is evidenced by an intracellular change in calcium concentration, mediated by nitric oxide-responsive plasma membrane channel proteins. PMID:24158008
NSDL National Science Digital Library
Olivia Worland (Purdue University; Biological Sciences)
2008-06-06
Coordination is an organized working together of muscles and groups of muscles aimed at bringing about a purposeful movement such as walking or standing. Coordination involves timing and concentration.
NSDL National Science Digital Library
David Stern
This introduction to the labeling of points on a plane by their Cartesian coordinates can optionally be extended to coordinates in 3-dimensional space, to plane polar coordinates and to 3-dimensional polar coordinates. Students should learn to use Cartesian coordinates (x,y) for defining the position of a point in two dimensions and to use Cartesian coordinates (x,y,z) in 3-dimensional space and learn to appreciate the two ways of defining the z axis. Students should also become familiar with some of the tools and terms used by surveyors such as theodolite, azimuth, elevation, and zenith. Optional items for students familiar with trigonometry and with the theorem of Pythagoras are polar coordinates (r,f ) on the plane, Converting (r,f) to (x,y) and vice versa, at least for r, and Spherical polar coordinates (r,q, f) in 3-dimensional space.
Preparation of PbS and PbO nanopowders from new Pb(II)(saccharine) coordination polymers
NASA Astrophysics Data System (ADS)
Aslani, Alireza; Musevi, Seyid Javad; ?ahin, Ertan; Yilmaz, Veysel T.
2014-11-01
Nanopowders and single crystal of new Pb(II) three-dimensional coordination polymer, [Pb(H2O)(?-OAc)(?-sac)]n "PASAC" were synthesized by a sonochemical and branched tube methods (Y?lmaz et al., Z. Anorg. Allg. Chem. 629 (2003) 172). The new nano-structures of Pb(II) coordination polymer were characterized by X-ray crystallography analysis, scanning electron microscopy (SEM), X-ray powder diffraction (XRD), surface analysis (BET), and IR spectroscopy. The crystal structure of these compounds consists of three-dimensional polymeric units. The thermal stability of compounds was studied by thermal gravimetric analysis (TGA) and differential thermal analyses (DTA). PbS and PbO nano-structures were obtained by calcinations of the nano-structures of this coordination polymer at 600 °C.
Puzzo, Daniel P; Scotognella, Francesco; Zavelani-Rossi, Margherita; Sebastian, Maria; Lough, Alan J; Manners, Ian; Lanzani, Guglielmo; Tubino, Riccardo; Ozin, Geoffrey A
2009-12-01
Nanoparticle one-dimensional photonic crystals exhibit intense, broadband reflectivity coupled with a unique mesoporosity. The latter property allows for infiltration of the one-dimensional photonic crystal with functional materials, such as emitting polymers, which in turn can lead to the fabrication of composites whereby the emitter's emission can be modulated by the photon density of states of the photonic crystal. We exploit this interaction in order to produce efficient distributed feedback lasing from a composite poly(phenylene vinylene)-infiltrated nanoparticle one-dimensional photonic crystal. PMID:19842702
NASA Astrophysics Data System (ADS)
Han, Yinfeng; Wang, Chang`an; Zheng, Zebao; Sun, Jiafeng; Nie, Kun; Zuo, Jian; Zhang, Jianping
2015-07-01
Two coordination polymers, {[Mn2(L1)2(?2-H2O)(H2O)4]·5H2O}n 1 and {[Ni(L1)(H2O)2]·2H2O}n 2 (H2L1=2,2?-dithiobisnicotinic acid), were prepared by the solvothermal reactions of the Mn(II) or Ni(II) ions with 2-mercaptonanicotinic acid. In 1, the [Mn2(COO)4] units are connected by the 2,2?-dithiobisnicotinic dianion to form a two-dimensional (4,4)-connected network. In 2, the adjacent Ni(II) ions are connected by the carboxyl groups of the 2,2?-dithiobisnicotinic dianion to form an one-dimensional inorganic rod-shaped chain [Ni(COO)2]n, which are further interconnected by the 2,2?-dithiobisnicotinic ligand, giving rise to a two-dimensional framework. Variable-temperature magnetic susceptibilities of 1 and 2 exhibit overall weak antiferromagnetic coupling between the adjacent metal ions.
NASA Astrophysics Data System (ADS)
Saravanakumar, Rajendran; Varghese, Babu; Sankararaman, Sethuraman
2014-11-01
Using phenylpropynoic acid (PPA) and 1,4-diazabicyclo[2.2.2]octane (DABCO) as organic spacers, isostructural coordination polymers of Zn(II), Cd(II) and Cu(II) were synthesized by solvothermal method and structurally characterized using single crystal XRD, powder XRD, 13C CP-MAS NMR spectroscopy. Single crystal XRD data revealed four PPA units coordinating with two metal ions forming a paddle wheel secondary building unit (SBU). The paddle wheel units are connected through coordination of DABCO nitrogen to the metal centers from the axial positions leading to the formation of the 1D coordination polymers along the c axis. Intermolecular ? stacking and Csbnd H…? interactions between the adjacent polymer chains convert the 1D coordination polymer into an interesting 3D network with the Csbnd H…? bonds running along the crystallographic a and b axes. Thermal and nitrogen adsorption studies of these coordination polymers are reported.
Y. A. Aggour; M. S. Aziz; M. I. Youssif
2000-01-01
The coordinated polymer of poly(ethylene glycol) alleneyl methyl ether (PEGA) with iron (III) chloride (PEGA-FeCl3) was prepared by radical mechanism and characterized by infrared spectroscopy and elemental analyses. The electrical properties were studied using D.C. electrical conductivity. The relationship between the activation energy (?E) and the temperature are given to illustrate the behaviour of the polymer. Investigation of the A.C.
NASA Astrophysics Data System (ADS)
Han, Yinfeng; Zheng, Zebao; Wang, Chang'an; Sun, Jiafeng; Li, Xiaoyan; Zhang, Jianping; Xiao, Jing; He, Guofang; Li, Liqing
2015-01-01
A CuII coordination polymer, [Cu(sbpc)(phen)(H2O)]?H2O 1, has been synthesized and characterized structurally and magnetically (H2sbpc = 4-sulfobiphenyl-4?-carboxylic acid, phen = 1,10-phenanthroline). Single-crystal structural analysis shows that 1 consists of dinuclear [Cu2(CO2)2] units bridged via sbpc2- to afford a 1-D chain, which then extends into the 3-D coordination polymer supramolecular network by O-H⋯O hydrogen bonds and ?⋯? interactions. Magnetic measurements indicate that complex 1 exhibits weak antiferromagnetic coupling.
Short range correlations in a one dimensional electron gas
Murat Tas; Mehmet Tomak
2001-01-01
We use the SSTL (Singwi, Sjolander, Tosi, Land) approximation to investigate the short--range correlations in a one dimensional electron gas, for the first time. Although SSTL is introduced to better satisfy the compressibility sum rule in three dimensions, the widely used STLS (Singwi, Tosi, Land, Sjolander) approximation turns out to be more successful in the case of the one dimensional
QUASISTATIONARY DISTRIBUTIONS FOR ONE-DIMENSIONAL DIFFUSIONS WITH KILLING
Evans, Steven N.
QUASISTATIONARY DISTRIBUTIONS FOR ONE-DIMENSIONAL DIFFUSIONS WITH KILLING DAVID STEINSALTZ AND STEVEN N. EVANS Abstract. We extend some results on the convergence of one-dimensional diffusions killed at the boundary, conditioned on extended survival, to the case of general killing on the interior. We show, under
One-dimensional boron nanostructures: Prediction, synthesis, characterizations, and applications
Gao, Hongjun
One-dimensional boron nanostructures: Prediction, synthesis, characterizations, and applications January 2010, Accepted 24th March 2010 DOI: 10.1039/c0nr00051e One-dimensional (1D) boron nanostructures nanomaterials. In this article, we review the current progress that has been made on 1D boron nanostructures
Dynamic Response Localization in One-Dimensional Periodic Systems
Phani, A. Srikantha
Dynamic Response Localization in One-Dimensional Periodic Systems by Lalitha Raghavan B.E, Osmania in advanced periodic light weight material and structural systems. One-dimensional structural systems are used that the introduction of periodic local resonators narrows Bragg bandgaps above the lo- cal resonant bandgap
MULTIPLICITY FREE SPACES WITH A ONE DIMENSIONAL HUBERT RUBENTHALER
Paris-Sud XI, Université de
MULTIPLICITY FREE SPACES WITH A ONE DIMENSIONAL QUOTIENT HUBERT RUBENTHALER Abstract. The multiplicity free spaces with a one dimensional quotient were introduced by Thierry Levasseur in [11]. Recently. Introduction 1 2. Multiplicity free spaces. Basic definitions and properties 2 2.1. Prehomogeneous Vector
Wang, Yin Lin; Long, Ling Liang; Zhang, Jin Fang
2015-06-01
A two-dimensional Mn(II) coordination polymer (CP), poly[bis[?2-2,6-bis(imidazol-1-yl)pyridine-?(2)N(3):N(3')]bis(thiocyanato-?N)manganese] [Mn(NCS)2(C11H9N5)2]n, (I), has been obtained by the self-assembly reaction of Mn(ClO4)2·6H2O, NH4SCN and bent 2,6-bis(imidazol-1-yl)pyridine (2,6-bip). CP (I) was characterized by FT-IR spectroscopy, elemental analysis and single-crystal X-ray diffraction. The crystal structure features a unique two-dimensional (4,4) network with one-dimensional channels. The luminescence and nitrobenzene-sensing properties were explored in a DMF suspension, revealing that CP (I) shows a strong luminescence emission and is highly sensitive for nitrobenzene detection. PMID:26044322
Hardening transition in a one-dimensional model for ferrogels
NASA Astrophysics Data System (ADS)
Annunziata, Mario Alberto; Menzel, Andreas M.; Löwen, Hartmut
2013-05-01
We introduce and investigate a coarse-grained model for quasi one-dimensional ferrogels. In our description the magnetic particles are represented by hard spheres with a magnetic dipole moment in their centers. Harmonic springs connecting these spheres mimic the presence of a cross-linked polymer matrix. A special emphasis is put on the coupling of the dipolar orientations to the elastic deformations of the matrix, where a memory effect of the orientations is included. Although the particles are displaced along one spatial direction only, the system already shows rich behavior: as a function of the magnetic dipole moment, we find a phase transition between "soft-elastic" states with finite interparticle separation and finite compressive elastic modulus on the one hand, and "hardened" states with touching particles and therefore diverging compressive elastic modulus on the other hand. Corresponding phase diagrams are derived neglecting thermal fluctuations of the magnetic particles. In addition, we consider a situation in which a spatially homogeneous magnetization is initially imprinted into the material. Depending on the strength of the magneto-mechanical coupling between the dipole orientations and the elastic deformations, the system then relaxes to a uniaxially ferromagnetic, an antiferromagnetic, or a spiral state of magnetization to minimize its energy. One purpose of our work is to provide a largely analytically solvable approach that can provide a benchmark to test future descriptions of higher complexity. From an applied point of view, our results could be exploited, for example, for the construction of novel damping devices of tunable shock absorbance.
Boyer, Edmond
L-247 Complete devil's staircase in the one-dimensional lattice gas Comment on « one-dimensional lattice gas and the universality of the devil's staircase » bv S. E. Burkov S. Aubry Laboratoire Léon of the complete devil's staircase for the lattice gas model. Thus, we show that the behaviour at the commensurate
Ying, Shao Ming; Ru, Jing Jing; Luo, Wu Kui
2015-07-01
Metal-organic frameworks (MOFs) have potentially useful applications and an intriguing variety of architectures and topologies. Two homochiral coordination polymers have been synthesized by the hydrothermal method, namely poly[(?-N-benzyl-L-phenylalaninato-?(4)O,O':O,N)(?-formato-?(2)O:O')zinc(II)], [Zn(C16H16NO2)(HCOO)]n, (1), and poly[(?-N-benzyl-L-leucinato-?(4)O,O':O,N)(?-formato-?(2)O:O')zinc(II)], [Zn(C13H18NO2)(HCOO)]n, (2), and studied by single-crystal X-ray diffraction, elemental analyses, IR spectroscopy and fluorescence spectroscopy. Compounds (1) and (2) each have a two-dimensional layer structure, with the benzyl or isobutyl groups of the ligands directed towards the interlayer interface. Photoluminescence investigations show that both (1) and (2) display a strong emission in the blue region. PMID:26146402
Zheng, Xiu-Ying; Zhang, Han; Cao, Ling-Yun; Kong, Xiang-Jian; Long, La-Sheng; Zheng, Lan-Sun
2015-03-28
Two enantiomorphic 3D lanthanide coordination polymers of {[Dy5(L)4(H2O)10][Dy(H2O)7][Na(H2O)5]}·(ClO4)7·(H2O)15 (1a for R and 1b for S) with chiral helical chains were synthesized based on an achiral ligand N-(2-hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid (H3L) and Dy(ClO4)3. Crystal analysis revealed that 1a and 1b were crystallized in chiral space groups P4132 and P4332, respectively. The absolute configurations of the two structures were evidenced by vibrational circular dichroism (VCD) spectra with one single crystal sample. PMID:25710701
Pressure Sensor via Optical Detection Based on a 1D Spin Transition Coordination Polymer
Jureschi, C?t?lin M.; Linares, Jorge; Rotaru, Aurelian; Ritti, Marie Hélène; Parlier, Michel; Dîrtu, Marinela M.; Wolff, Mariusz; Garcia, Yann
2015-01-01
We have investigated the suitability of using the 1D spin crossover coordination polymer [Fe(4-(2?-hydroxyethyl)-1,2,4-triazole)3]I2·H2O, known to crossover around room temperature, as a pressure sensor via optical detection using various contact pressures up to 250 MPa. A dramatic persistent colour change is observed. The experimental data, obtained by calorimetric and Mössbauer measurements, have been used for a theoretical analysis, in the framework of the Ising-like model, of the thermal and pressure induced spin state switching. The pressure (P)-temperature (T) phase diagram calculated for this compound has been used to obtain the P-T bistability region. PMID:25621610
Pressure sensor via optical detection based on a 1D spin transition coordination polymer.
Jureschi, C?t?lin M; Linares, Jorge; Rotaru, Aurelian; Ritti, Marie Hélène; Parlier, Michel; Dîrtu, Marinela M; Wolff, Mariusz; Garcia, Yann
2015-01-01
We have investigated the suitability of using the 1D spin crossover coordination polymer [Fe(4-(2'-hydroxyethyl)-1,2,4-triazole)3]I2?H2O, known to crossover around room temperature, as a pressure sensor via optical detection using various contact pressures up to 250 MPa. A dramatic persistent colour change is observed. The experimental data, obtained by calorimetric and Mössbauer measurements, have been used for a theoretical analysis, in the framework of the Ising-like model, of the thermal and pressure induced spin state switching. The pressure (P)-temperature (T) phase diagram calculated for this compound has been used to obtain the P-T bistability region. PMID:25621610
Hua Wu; LaiPing Zhang; HaiYan Liu; Jin Yang; JianFang Ma
2009-01-01
Six new coordination polymers constructed from two structurally related ligands, 2,2?-bis(2-methylbenzimidazole) ether (L1)\\u000a and 2,2?-bis(2-ethylbenzimidazole)ether (L2), have been synthesized. They are [Cu(L1)(bz)2] (1), [Cu(L2)(bz)2] (2), [Zn2(L1)(m-bdc)2] (3), [Cd2(L2)(m-bdc)2(H2O)]2·H2O (4), [Zn(L1)(OH-bdc)-(H2O)] (5) and [Zn2(L2)(btca)] (6), where Hbz = benzoic acid, m-H2bdc = 1,3-benzenedicarboxylic acid, OH-H2bdc = 5-hydroxyisophthalic acid, and H4btca = 1,2,4,5-benzenetetracarboxylic acid. In 1 and 2, the bidentate N-donor ligands
NASA Astrophysics Data System (ADS)
Jiang, Ya-Hui; Wu, Wei-Ping; Yang, Guo-Ping; Jin, Jun-Cheng; Xi, Zheng-Ping; Wang, Yao-Yu
2015-07-01
Three new coordination polymers (CPs) based on rigid ligand 5-Aminonicotinic acid (5-anaH), [Cd(5-ana)2]·(H2O)2 (1), [Cd(5-ana)(HCOO) ] (2) and [Cu(5-ana)2] (3), have been synthesized under different solvent media and temperatures. All CPs are characterized by single crystal X-ray diffraction, elemental analysis, IR spectroscopy, powder X-ray diffraction and thermogravimetric analysis. Compound 1 is a two-dimensional (2D) (4,4)-connected layered structure contains 1D open channels. 2 shows a 2-nodal (3,5)-connected three-dimensional (3D) framework with {52·6}{53·63·73·8} topology. While 3 displays a 3D (3,6)-connected homochiral framework with {42·6}2{44·62·85·104} topology. The solid-state photoluminescence for 1 and 2 were also studied.
A systematic study on the stability of porous coordination polymers against ammonia.
Kajiwara, Takashi; Higuchi, Masakazu; Watanabe, Daisuke; Higashimura, Hideyuki; Yamada, Teppei; Kitagawa, Hiroshi
2014-11-17
To establish a strategy for designing porous coordination polymers (PCPs) for ammonia capture, the first systematic study on the stability of PCPs against ammonia was conducted. Various types of PCPs were investigated by comparing their powder XRD patterns before and after treatment with ammonia. Among the PCPs tested, ZIF-8, MIL-53(Al), Al-BTB, MOF-76(M) (M=Y or Yb), MIL-101(Cr), and MOF-74(Mg) were stable up to 350?°C under an ammonia atmosphere at ambient pressure. The origin of the stability of PCPs is discussed from the viewpoint of their components, metal cations, and organic linkers. Furthermore, adsorption isotherm measurements show that the adsorptive behavior of PCPs is independent of their stability. PMID:25313521
Kondo, Mio; Furukawa, Shuhei; Hirai, Kenji; Tsuruoka, Takaaki; Reboul, Julien; Uehara, Hiromitsu; Diring, Stéphane; Sakata, Yoko; Sakata, Osami; Kitagawa, Susumu
2014-04-01
Structural transformability accompanied by molecular accommodation is a distinguished feature of porous coordination polymers (PCPs) among porous materials. Conventional X-ray crystallography allows for the determination of each structural phase emerged during transformation. However, the propagation mechanism of transformation through an entire crystal still remains in question. Here we elucidate the structural nature of the spatial transient state, in which two different but correlated framework structures, an original phase and a deformed phase, simultaneously exist in one crystal. The deformed phase is distinctively generated only at the crystal surface region by introducing large guest molecules, while the remaining part of crystal containing small molecules maintains the original phase. By means of grazing incidence diffraction techniques we determine that the framework is sheared with sharing one edge of the original primitive cubic structure, leading to the formation of crystal domains with four mirror image relationships. PMID:24611471
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.
NASA Astrophysics Data System (ADS)
Chen, Jinxi; Wang, Jingjing; Ohba, Masaaki
2012-01-01
Two manganese coordination polymers, [Mn2(ip)2(dmf)]·dmf (1) and [Mn4(ip)4(dmf)6]·2dmf (2) (ip=isophthalate; dmf=N,N-dimethylformamide), have been synthesized and characterized. X-ray crystal structural data reveal that compound 1 crystallizes in triclinic space group P-1, a=9.716(3) Å, b=12.193(3) Å, c=12.576(3) Å, ?=62.19(2)°, ?=66.423(17)°, ?=72.72(2)°, Z=2, while compound 2 crystallizes in monoclinic space group Cc, a=19.80(3) Å, b=20.20(2) Å, c=18.01(3) Å, ?=108.40(4)°, Z=4. Variable-temperature magnetic susceptibilities of compounds 1 and 2 exhibit overall weak antiferromagnetic coupling between the adjacent Mn(II) ions.
W. B. Gurnule; L. J. Paliwal; R. B. Kharat
2003-01-01
Coordination polymers of Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) with the 1,2?bis?(4?thio?1,3,5?hexahydro?1?triazinyl)ethane (H2BTHTE) ligand have been prepared in DMF solution. The coordination polymers have been characterized by their elemental analyses, magnetic susceptibility and by electronic and infrared spectral measurements. The thermal stability of each polymer was determined by thermogravimetric analysis. The thermal stability of the coordination polymers obtained from
Evstifeev, I. E.; Kiskin, M. A., E-mail: mkiskin@igic.ras.ru [Russian Academy of Sciences, Kurnakov Institute of General and Inorganic Chemistry (Russian Federation); Bogomyakov, A. S. [Russian Academy of Sciences, International Tomography Center, Siberian Branch (Russian Federation); Sidorov, A. A.; Novotortsev, V. M.; Eremenko, I. L. [Russian Academy of Sciences, Kurnakov Institute of General and Inorganic Chemistry (Russian Federation)
2011-09-15
Reactions between lithium pivalate and cobalt coordination polymers [Co{sub 5}(OH{sub 2})(OH)(Piv){sub 9})L{sup 1}){sub 4}]{sub n} (I) and [Co{sub 2}(OH{sub 2})(Piv){sub 4}(L{sup 2}){sub 2}]{sub n} (II), where Piv-is the pivalate anion, L{sup 1} is pyrazine, and L{sup 2} is pyrimidine, result in new heterometallic polymers {l_brace}[Li{sub 2}Co{sub 2}(Piv){sub 6}(L{sup 1}){sub 2}]{sub 2}MeCN{r_brace}{sub n} (III), {l_brace}[Li{sub 2}Co{sub 2}(Piv){sub 6}(L{sup 2})]{sub 0.5}MeCN{r_brace}{sub n} (IV), and [Li{sub 2}Co{sub 2}(Piv){sub 6}(L{sup 2}){sub 2}]{sub n} (V). The resulting compounds contain tetra-nuclear {l_brace}Li{sub 2}Co{sub 2}(Piv){sub 6}{r_brace} fragments connected by neutral bridging ligands (pyrazine or pyrimidine) into layer structures. Crystal structures III-V are determined, and the magnetic properties of III and IV are studied.
Novio, Fernando; Lorenzo, Julia; Nador, Fabiana; Wnuk, Karolina; Ruiz-Molina, Daniel
2014-11-17
Functionalization of nanoparticles can significantly influence their properties and potential applications. Although researchers can now functionalize metal, metal oxide, and organic polymer nanoparticles with a high degree of precision, controlled surface functionalization of nanoscale coordination polymer particles (CPPs) has remained a significant challenge. The lack of methodology is perhaps one of the greatest roadblocks to the advancement of CPPs into high added-value drug delivery applications. Here, we report having achieved this goal through a stepwise formation and functionalization protocol. We fabricated robust nanoparticles with enhanced thermal and colloidal stabilities by incorporation of carboxyl groups and these surface carboxyl groups could be subsequently functionalized through well-known peptide coupling reactions. The set of chemistries that we employed as proof-of-concept enabled a plethora of new functional improvements for the application of CPPs as drug delivery carriers, including enhanced colloidal stabilities and the incorporation of additional functional groups such as polyethylene glycol (PEG) or fluorescent dyes that enabled tracking of their cellular uptake. Finally, we ascertained the cytotoxicity of the new CPP nanoparticles loaded with camptothecin to human breast adenocarcinoma (MCF-7). Efflux measurements show that the encapsulation of camptothecin enhances the potency of the drug 6.5-fold and increases the drug retention within the cell. PMID:25284328
Spectroscopy of one-dimensionally inhomogeneous media with quadratic nonlinearity
Golubkov, A A; Makarov, Vladimir A
2011-11-30
We present a brief review of the results of fifty years of development efforts in spectroscopy of one-dimensionally inhomogeneous media with quadratic nonlinearity. The recent original results obtained by the authors show the fundamental possibility of determining, from experimental data, the coordinate dependences of complex quadratic susceptibility tensor components of a onedimensionally inhomogeneous (along the z axis) medium with an arbitrary frequency dispersion, if the linear dielectric properties of the medium also vary along the z axis and are described by a diagonal tensor of the linear dielectric constant. It is assumed that the medium in question has the form of a plane-parallel plate, whose surfaces are perpendicular to the direction of the inhomogeneity. Using the example of several components of the tensors X{sup (2)}(z, {omega}{sub 1} {+-} {omega}{sub 2}; {omega}{sub 1}, {+-} {omega}{sub 2}), we describe two methods for finding their spatial profiles, which differ in the interaction geometry of plane monochromatic fundamental waves with frequencies {omega}{sub 1} and {omega}{sub 2}. The both methods are based on assessing the intensity of the waves propagating from the plate at the sum or difference frequency and require measurements over a range of angles of incidence of the fundamental waves. Such measurements include two series of additional estimates of the intensities of the waves generated under special conditions by using the test and additional reference plates, which eliminates the need for complicated phase measurements of the complex amplitudes of the waves at the sum (difference) frequency.
Exact solution of the one-dimensional Hubbard model with arbitrary boundary magnetic fields
NASA Astrophysics Data System (ADS)
Li, Yuan-Yuan; Cao, Junpeng; Yang, Wen-Li; Shi, Kangjie; Wang, Yupeng
2014-02-01
The one-dimensional Hubbard model with arbitrary boundary magnetic fields is solved exactly via the Bethe ansatz methods. With the coordinate Bethe ansatz in the charge sector, the second eigenvalue problem associated with the spin sector is constructed. It is shown that the second eigenvalue problem can be transformed into that of the inhomogeneous XXX spin chain with arbitrary boundary fields which can be solved via the off-diagonal Bethe ansatz method.
Zakaria, Mohamed B; Hu, Ming; Pramanik, Malay; Li, Cuiling; Tang, Jing; Aldalbahi, Ali; Alshehri, Saad M; Malgras, Victor; Yamauchi, Yusuke
2015-07-01
A straightforward strategy to prepare nanoporous metal oxides with well-defined shapes is highly desirable. Through thermal treatment and a proper selection of metal-cyanide coordination polymers, nanoporous nickel-cobalt mixed oxides with different shapes (i.e., flakes and cubes) can be easily prepared. Our nanoporous materials demonstrate high electrocatalytic activity for oxygen evolution reaction. PMID:25968597
Properties of a One-Dimensional Dirac Liquid
NASA Astrophysics Data System (ADS)
Gochan, Matthew; Stokes, James; Bedell, Kevin
2015-03-01
Recent experimental results, as well as technological implications, have lead to a resurgence in the analysis of one-dimensional systems. Of particular interest are the technological advances possible in one-dimensional systems; specifically carbon nano-tubes and nano-wires. Here we investigate the properties of a one-dimensional Dirac liquid. We show a distinct change in the behavior of the exponents of quantities such as the correlation functions, density of states, and momentum distribution function. We find that these exponents, as well as relevant thermodynamic and transport properties are independent of density. Additionally, we discuss the consequences the Virial Theorem has on such systems.
NASA Astrophysics Data System (ADS)
Näther, Christian; Greve, Jan; Jeß, Inke; Wickleder, Claudia
2003-08-01
The new copper(I) coordination polymers poly[(di- ?2-thiocyanato- N, S)-( ?2-2,5-dimethylpyrazine- N, N)] dicopper(I) ( I) and poly[di- ?2-thiocyanato- N, S)-( ?2-2,3-dimethyl-pyrazine- N, N)] dicopper(I) ( II) were prepared by the reaction of copper(I) thiocyanate with 2,3- and 2,5-dimethylpyrazine in acetonitrile. In all compounds different CuSCN sub-structures are found which are connected by the dimethylpyrazine ligands to multi-dimensional coordination networks. The thermal properties of all compounds were investigated using simultaneous differential thermoanalysis (DTA), thermogravimetry (TG) and mass spectrometry (MS) as well as temperature resolved X-ray powder diffraction. On heating, compound I and II loose all of the dimethylpyrazine ligands in an endothermic reaction and transform directly into copper(I) thiocyanate. Optical investigations show two excited states for both compounds in absorption and in luminescence measurements which are both, MC and LMCT in character.
NASA Astrophysics Data System (ADS)
Zhang, Xian-Ming; Tong, Ming-Liang; Lee, Hung Kay; Chen, Xiao-Ming
2001-08-01
Two isostructural vanadium(IV) coordination polymers [VO(dod)2]X2 [X=Cl, Br; dod=1,4-diazoniabicyclo[2,2,2] octane-1,4-diacetate (C10H16N2O4)] have been synthesized solvothermally and determined by single-crystal X-ray analysis. Both of them crystallize in the tetragonal space group P4/ncc (no. 130), with cell parameters a=15.702(5), c=9.745(5) Å, V=2403(2) Å3, Z=4 for 1 and a=15.916(5), c=9.820(4) Å, V=2488(2) Å3, Z=4 for 2. In both complexes, each vanadium atom adopts a VIVO5 square-pyramidal environment, being coordinated by four oxygen atoms [V-O=1.978(2) Å for 1 and 1.969(3) Å for 2] from four dod ligands and a terminal oxygen atom [V=O=1.580(5) Å for 1 and 1.572(7) Å for 2]. The bis-monodentate dod ligands bridge vanadium atoms to furnish two-dimensional double wave-like layers of (4,4) topological type. Along the c-axis direction, there are square channels constructed from side-sharing saddle-shaped rings. The microporous material 1 shows chloride-to-sulfate exchange properties in aqueous media.
NASA Astrophysics Data System (ADS)
O'Donovan, Megan E.; LaDuca, Robert L.
2014-07-01
Hydrothermal treatment of cadmium nitrate, 5-nitroisophthalic acid (H2nip) and one of two isomeric dipyridylamides resulted in coordination polymer crystalline solids that manifested different in situ reactivity and dimensionality, as ascertained by single crystal X-ray diffraction. Hydrolysis of 3-pyridylisonicotinamide (3-pina) afforded the 3-aminopyridine (3-ampyr) ligands observed in the 1-D ladder polymer {[Cd(nip)(3-ampyr)(H2O)]?2H2O}n (1). Conversely, hydrolysis of the isomeric precursor 3-pyridylnicotinamide (3-pna) generated the monoanionic nicotinate ligands in the 2-D coordination polymer [Cd2(nip)(nic)2(H2O)2]n (2). Compound 2 displays {Cd2(OCO)2} eight-membered ring dimeric units linked into (6,3) graphite-type slab motifs. Luminescent properties of these two new materials are also presented.
Hydrothermal reactions: From the synthesis of ligand to new lanthanide 3D-coordination polymers
Silva, Fausthon Fred da; Fernandes de Oliveira, Carlos Alberto; Lago Falcão, Eduardo Henrique [Laboratório de Terras Raras, Departamento de Química Fundamental, Universidade Federal de Pernambuco (DQF-UFPE), 50590-470 Recife, PE (Brazil); Gatto, Claudia Cristina [Laboratório de Síntese Inorgânica e Cristalografia, Instituto de Química, Universidade de Brasília (IQ-UnB), 70904-970 Brasilia, DF (Brazil); Bezerra da Costa, Nivan; Oliveira Freire, Ricardo [Pople Computational Chemistry Laboratory, Departamento de Química, Universidade Federal de Sergipe, São Cristóvão-SE 49100-000 (Brazil); Chojnacki, Jaros?aw [Department of Inorganic Chemistry, Gdansk University of Technology, 80-233 Gdansk (Poland); Alves Júnior, Severino, E-mail: salvesjr@ufpe.br [Laboratório de Terras Raras, Departamento de Química Fundamental, Universidade Federal de Pernambuco (DQF-UFPE), 50590-470 Recife, PE (Brazil)
2013-11-15
The organic ligand 2,5-piperazinedione-1,4-diacetic acid (H{sub 2}PDA) was synthesized under hydrothermal conditions starting from the iminodiacetic acid and catalyzed by oxalic acid. The X-ray powder diffraction data indicates that the compound crystallizes in the P2{sub 1}/c monoclinic system as reported in the literature. The ligand was also characterized by elemental analysis, magnetic nuclear resonance, infrared spectroscopy and thermogravimetric analysis. Two new coordination networks based on lanthanide ions were obtained with this ligand using hydrothermal reaction. In addition to single-crystal X-ray diffraction, the compounds were characterized by infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy and elemental analysis. Single-crystal XRD showed that the compounds are isostructural, crystallizing in P2{sub 1}/n monoclinic system with chemical formula [Ln(PDA){sub 1.5}(H{sub 2}O)](H{sub 2}O){sub 3} (Ln=Gd{sup 3+}(1) and Eu{sup 3+}(2)).The luminescence properties of both compounds were studied. In the compound (1), a broad emission band was observed at 479 nm, redshifted by 70 nm in comparison of the free ligand. In (2), the typical f–f transition was observed with a maximum peak at 618 nm, related with the red emission of the europium ions. Computational methods were performed to simulate the crystal structure of (2). The theoretical calculations of the intensity parameters are in good agreement with the experimental values. - Graphical abstract: Scheme of obtaining the ligand 2,5-piperazinedione-1,4-diacetic acid (H{sub 2}PDA) and two new isostructural 3D-coordination polymers [Ln(PDA){sub 1.5}(H{sub 2}O)](H{sub 2}O){sub 3} (Ln=Gd{sup 3+} and Eu{sup 3+}) by hydrothermal synthesis. Display Omitted - Highlights: • The ligand 2,5-piperazinedione-1,4-diacetic acid was synthetized using the hydrothermic method and characterized. • Two new 3D-coordination polymers with this ligand containing Gd{sup 3+} and Eu{sup 3+} ions were also obtained. • The compounds are isostructural and the typical luminescent properties were observed in both structures.
Computation of the one-dimensional unwrapped phase
Karam, Zahi Nadim
2006-01-01
In this thesis, the computation of the unwrapped phase of the discrete-time Fourier transform (DTFT) of a one-dimensional finite-length signal is explored. The phase of the DTFT is not unique, and may contain integer ...
Defect modes in one-dimensional granular crystals
Boechler, Nicholas Sebastian
We study the vibrational spectra of one-dimensional statically compressed granular crystals (arrays of elastic particles in contact) containing light-mass defects. We focus on the prototypical settings of one or two spherical ...
NSDL National Science Digital Library
In this activity, developed by the Lane Community College Geo-STAC programâ??, students "understand geographic location (absolute and relative) using an interactive Web-based GIS map." The lesson helps review basic concepts of coordinate geometry as they move about the world identifying coordinate relationships and important reference lines. On the site, visitors will find a link to the student activity and teaching guide, as well as link to the web-based GIS map. This is an excellent activity for high school or early undergraduate students for hands-on work with GIS and coordinate systems.
zur Loye, Hans-Conrad
-dimensional mixed-metal polymer chains in the crystalline state. The magnetic susceptibilities of 2 and 3 wereMetal-Containing Ligands for Mixed-Metal Polymers: Novel Cu(II)-Ag(I) Mixed-Metal Coordination Polymers Generated from [Cu(2-methylpyrazine-5-carboxylate)2(H2O)],3H2O and Silver(I) Salts Yu-Bin Dong
Quantum Correlation in One-dimensional Extend Quantum Compass Model
Wen-Long You
2012-02-04
We study the correlations in the one-dimensional extended quantum compass model in a transverse magnetic field. By exactly solving the Hamiltonian, we find that the quantum correlation of the ground state of one-dimensional quantum compass model is vanishing. We show that quantum discord can not only locate the quantum critical points, but also discern the orders of phase transitions. Furthermore, entanglement quantified by concurrence is also compared.
Gigantic optical nonlinearity in one-dimensional Mott-Hubbard insulators
NASA Astrophysics Data System (ADS)
Kishida, H.; Matsuzaki, H.; Okamoto, H.; Manabe, T.; Yamashita, M.; Taguchi, Y.; Tokura, Y.
2000-06-01
The realization of all-optical switching, modulating and computing devices is an important goal in modern optical technology. Nonlinear optical materials with large third-order nonlinear susceptibilities (?(3)) are indispensable for such devices, because the magnitude of this quantity dominates the device performance. A key strategy in the development of new materials with large nonlinear susceptibilities is the exploration of quasi-one-dimensional systems, or `quantum wires'-the quantum confinement of electron-hole motion in one-dimensional space can enhance ? (3). Two types of chemically synthesized quantum wires have been extensively studied: the band insulators of silicon polymers, and Peierls insulators of ?-conjugated polymers and platinum halides. In these systems, ?(3) values of 10-12 to 10-7 e.s.u. (electrostatic system of units) have been reported. Here we demonstrate an anomalous enhancement of the third-order nonlinear susceptibility in a different category of quantum wires: one-dimensional Mott insulators of 3 d transition-metal oxides and halides. By analysing the electroreflectance spectra of these compounds, we measure ?(3) values in the range 10-8 to 10-5 e.s.u. The anomalous enhancement results from a large dipole moment between the lowest two excited states of these systems.
M. Thiel; M. Hermatschweiler; M. Wegener; G. von Freymann
2007-01-01
The recent experimental demonstration of polarization stop bands in three-dimensional dielectric circular-spiral photonic crystals is extended in two ways. First, the combination with a one-dimensional set of lamellae on one side allows for ``poor-man's optical isolators'' or for thin-film polarizers-depending on from which side light impinges onto the device. Second, a chiral three-dimensional photonic crystal sandwiched between two one-dimensional sets
M. A. Diab; A. Z. El-Sonbati; M. E. Attallah
2012-01-01
Novel polymeric complexes with a potentially bidentate ligand formed by amidation of 3,5-diamino-1,2,4-triazole with acryloyl chloride were synthesized and characterized on the basis of elemental analyses, IR, H-NMR, UV-Vis, magnetic susceptibility measurements, molar conductance, and thermal analyses. The molar conductance data reveal that all the polymer complexes are non-electrolytes. Spectral studies reveal that the free ligand coordinates bidentate to the
Zhou Ruisha; Cui Xiaobing; Song Jiangfeng; Xu Xiaoyu [College of Chemistry and State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, Changchun, Jilin 130021 (China); Xu Jiqing [College of Chemistry and State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, Changchun, Jilin 130021 (China)], E-mail: xjq@mail.jlu.edu.cn; Wang Tiegang [College of Chemistry and State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, Changchun, Jilin 130021 (China)
2008-08-15
A series of lanthanide coordination polymers, (Him){sub n}[Ln(ip){sub 2}(H{sub 2}O)]{sub n} [Ln=La(1), Pr(2), Nd(3) and Dy(4), H{sub 2}ip=isophthalic acid, im=imidazole] and [Y{sub 2}(ip){sub 3}(H{sub 2}O){sub 2}]{sub n}.nH{sub 2}O (5), have been synthesized and characterized by elemental analyses, infrared (IR), ultraviolet-visible-near infrared (UV-Vis-NIR) and single-crystal X-ray diffraction analyses. The isostructural compounds 1-4 possess 3-D structures with three different kinds of channels. Compound 5 features a 2-D network making of two different kinds of quadruple-helical chains. Compounds 2 and 3 present the characteristic emissions of Pr(III) and Nd(III) ions in NIR region, respectively. Compound 4 shows sensitized luminescence of Dy(III) ions in visible region. - Graphical abstract: A series of lanthanide coodination polymers, (Him){sub n}[Ln(ip){sub 2}(H{sub 2}O)]{sub n} [Ln=La(1), Pr(2), Nd(3) and Dy(4)] and [Y{sub 2}(ip){sub 3}(H{sub 2}O){sub 2}]{sub n}.nH{sub 2}O (5), have been reported. The isostructural compounds 1-4 possess 3-D structures with three different kinds of channels. Compound 5 displays a 2-D network making of two kinds of quadruple-helical chains. Display Omitted.
Feng, Xun; Feng, Yu-Quan; Liu, Lang; Wang, Li-Ya; Song, Hong-Liang; Ng, Seik-Weng
2013-06-01
A new zinc compound, together with a corresponding series of Zn-4f heterometallic coordination polymers, namely, [Zn(H2PBDA)(PBDA)]n (1), {[Ln2(PBDA)2·2H2O] [Zn2(PBDA)2Cl2]}n [H2PBDA = 3-(pyridin-3-yl-oxy) benzene-1,2-dicarboxylic acid, and Ln = Pr(2), Nd(3), Eu(4), Gd(5), Dy(6), Ho(7), Er(8)] have been hydrothermally synthesized and characterized systematically. Polymers 2-8 feature two-dimensional (2D) 4,4 networks, containing the original 1D heterometallic double stranded chains composed of [Ln2Zn2(PBDA)2] entities. The extensive hydrogen bonding and ?-? stacking interactions were observed to stabilize the extended architectures. The luminescence emission spectra of the polymers vary depending on the lanthanide(III) ion present. Informative magnetic susceptibility measurements show that the same carboxylate bridging fashion of the PBDA ligand results in the different magnetic properties occurring within the heterometallic coordination polymers. In addition, polymer 6 exhibits an interesting slow magnetic relaxation behavior at lower temperatures. PMID:23549773
Zhang, Bing; Liu, Bingqian; Chen, Guonan; Tang, Dianping
2015-02-15
Prostate-specific antigen (PSA), as a glycoprotein enzyme encoded in humans by the KLK3 gene, is one of the most important biomarkers for the diagnosis and prognosis of prostate cancer. Herein, a new electrochemical immunosensor for sensitive determination of PSA was designed by using redox and catalysis 'all-in-one' infinite coordination polymer (PtNP@ICP) as signal tag on the polyamidoamine dendrimers modified electrode interface. To construct such 'all-in-one' PtNP@ICP nanostructures, the coordination polymerization was fully carried between metal ions and polydentate bridging ligands, and the PtNP was encapsulated into the ICP in the process of polymerization. The prepared PtNP@ICP nanocatalyst was characterized by transmission electron microscope (TEM), energy dispersive X-ray spectrometry (EDX), ultraviolet and visible (UV-vis) spectrophotometry and Fourier transform infrared spectroscope (FTIR). And the synthesized PtNP@ICP was utilized as signal tag for the label of PSA. With a sandwich-type immunoassay format, the conjugated signal tag on the transducer increased with the increasing PSA concentration in the sample thus enhancing the signal of the electrochemical immunosensor due to the catalytic reduction toward H2O2 of the enveloped PtNP. Under optimal conditions, the current was proportional to the logarithm of PSA concentration ranging from 0.001 to 60 ng/mL. The detection limit (LOD) was 0.3 pg/mL at 3 sB. The immunosensor displayed an acceptable reproducibility, stability and selectivity. In addition, the methodology was evaluated with human serum specimens receiving good correlation with results from commercialized enzyme-linked immunosorbent assay (ELISA) method. PMID:25173732
Hirai, Kenji; Reboul, Julien; Morone, Nobuhiro; Heuser, John E; Furukawa, Shuhei; Kitagawa, Susumu
2014-10-22
Porous coordination polymers (PCPs) are an intriguing class of molecular-based materials because of the designability of framework scaffolds, pore sizes and pore surface functionalities. Besides the structural designability at the molecular scale, the structuring of PCPs into mesoscopic/macroscopic morphologies has attracted much attention due to the significance for the practical applications. The structuring of PCPs at the mesoscopic/macroscopic scale has been so far demonstrated by the spatial localization of coordination reactions on the surface of templates or at the phase boundaries. However, these methodologies have never been applied to the fabrication of solid-solution or multivariate metal-organic frameworks (MOFs), in which multiple components are homogeneously mixed. Herein, we demonstrate the structuring of a box-type superstructure comprising of a solid-solution PCP by integrating a bidirectional diffusion of multiple organic ligands into molecular assembly. The parent crystals of [Zn2(ndc)2(bpy)]n were placed in the DMF solution of additional organic component of H2bdc, and the temperature was rapidly elevated up to 80 °C (ndc = 1,4-naphthalenedicarboxylate, bpy = 4,4'-bipyridyl, bdc = 1,4-benzenedicarboxylate). The dissolution of the parent crystals induced the outward diffusion of components; contrariwise, the accumulation of the other organic ligand of H2bdc induced the inward diffusion toward the surface of the parent crystals. This bidirectional diffusion of multiple components spatially localized the recrystallization at the surface of cuboid parent crystals; therefore, the nanocrystals of a solid-solution PCP ([Zn2(bdc)1.5(ndc)0.5(bpy)]n) were organized into a mesoscopic box superstructure. Furthermore, we demonstrated that the box superstructures enhanced the mass transfer kinetics for the separation of hydrocarbons. PMID:25254320
Manna, Biplab; Anothumakkool, Bihag; Desai, Aamod V; Samanta, Partha; Kurungot, Sreekumar; Ghosh, Sujit K
2015-06-01
A new function of metal-sulfate-based coordination polymer (CP) for proton conduction was investigated through rational integration of a continuous water array and protonated amine in the coordination space of the CP. The H-bonded arrays of water molecules along with nitrogen-rich aromatic cation (protonated melamine) facilitate proton conduction in the compound under humid conditions. Although several reports of metal-oxalate/phosphate-based CPs showing proton conduction are known, this is the first designed synthesis of a metal-sulfate-based CP bearing water arrays functioning as a solid-state proton conductor. PMID:25985048
Shyamapada Shit; Joy Chakraborty; Soma Sen; Guillaume Pilet; Cédric Desplanches; Samiran Mitra
2008-01-01
A novel 1D coordination chain polymer {[Cu2(pydc)2(1,10-phen)(H2O)2]·3H2O}n (pydc=pyridine-2,3-dicarboxylate, 1,10-phen=1,10-phenantroline) has been synthesised and characterised by elemental analysis, FT-IR spectrum, thermal analysis and variable temperature magnetic susceptibility studies. Single crystal X-ray diffraction measurement of the complex shows two Cu(II) centres are in distorted square pyramidal geometry. The complex shows very interesting hydrogen bonding modes involving the lattice and coordinated water molecules
The nature of one-dimensional carbon: polyynic versus cumulenic.
Neiss, Christian; Trushin, Egor; Görling, Andreas
2014-08-25
A question of both fundamental as well as practical importance is the nature of one-dimensional carbon, in particular whether a one-dimensional carbon allotrope is polyynic or cumulenic, that is, whether bond-length alternation occurs or not. By combining the concept of aromaticity and antiaromaticity with the rule of Peierls distortion, the occurrence and magnitude of bond-length alternation in carbon chains with periodic boundary conditions and corresponding carbon rings as a function of the chain or ring length can be explained. The electronic properties of one-dimensional carbon depend crucially on the bond-length alternation. Whereas it is generally accepted that carbon chains in the limit of infinite length have a polyynic structure at the minimum of the potential energy surface with bond-length alternation, we show here that zero-point vibrations lead to an effective equalization of all carbon-carbon bond lengths and thus to a cumulenic structure. PMID:24962252
Porous coordination polymers with ubiquitous and biocompatible metals and a neutral bridging ligand
Noro, Shin-ichiro; Mizutani, Junya; Hijikata, Yuh; Matsuda, Ryotaro; Sato, Hiroshi; Kitagawa, Susumu; Sugimoto, Kunihisa; Inubushi, Yasutaka; Kubo, Kazuya; Nakamura, Takayoshi
2015-01-01
The design of inexpensive and less toxic porous coordination polymers (PCPs) that show selective adsorption or high adsorption capacity is a critical issue in research on applicable porous materials. Although use of Group II magnesium(II) and calcium(II) ions as building blocks could provide cheaper materials and lead to enhanced biocompatibility, examples of magnesium(II) and calcium(II) PCPs are extremely limited compared with commonly used transition metal ones, because neutral bridging ligands have not been available for magnesium(II) and calcium(II) ions. Here we report a rationally designed neutral and charge-polarized bridging ligand as a new partner for magnesium(II) and calcium(II) ions. The three-dimensional magnesium(II) and calcium(II) PCPs synthesized using such a neutral ligand are stable and show selective adsorption and separation of carbon dioxide over methane at ambient temperature. This synthetic approach allows the structural diversification of Group II magnesium(II) and calcium(II) PCPs. PMID:25592677
Chen Jinxi, E-mail: chenjinxi@seu.edu.cn [School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189 (China); Wang Jingjing [School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189 (China); Ohba, Masaaki [Department of Chemistry, Faculty of Science, Kyushu University, Fukuoka (Japan)
2012-01-15
Two manganese coordination polymers, [Mn{sub 2}(ip){sub 2}(dmf)]{center_dot}dmf (1) and [Mn{sub 4}(ip){sub 4}(dmf){sub 6}]{center_dot}2dmf (2) (ip=isophthalate; dmf=N,N-dimethylformamide), have been synthesized and characterized. X-ray crystal structural data reveal that compound 1 crystallizes in triclinic space group P-1, a=9.716(3) A, b=12.193(3) A, c=12.576(3) A, {alpha}=62.19(2) Degree-Sign , {beta}=66.423(17) Degree-Sign , {gamma}=72.72(2) Degree-Sign , Z=2, while compound 2 crystallizes in monoclinic space group Cc, a=19.80(3) A, b=20.20(2) A, c=18.01(3) A, {beta}=108.40(4) Degree-Sign , Z=4. Variable-temperature magnetic susceptibilities of compounds 1 and 2 exhibit overall weak antiferromagnetic coupling between the adjacent Mn(II) ions. - Graphical abstract: Three-dimensional porous and two-dimensional layered manganese isophthalates have been prepared. Magnetic susceptibility measurements exhibit overall weak antiferromagnetic interactions between the Mn(II) ions in both compounds. Highlights: Black-Right-Pointing-Pointer Two manganese isophthalates have been prepared. Black-Right-Pointing-Pointer Compound 1 adopts a three-dimensional porous structure. Black-Right-Pointing-Pointer Compound 2 adopts a two-dimensional layered structure. Black-Right-Pointing-Pointer Magnetic properties of both compounds are investigated.
Porous coordination polymers with ubiquitous and biocompatible metals and a neutral bridging ligand
NASA Astrophysics Data System (ADS)
Noro, Shin-Ichiro; Mizutani, Junya; Hijikata, Yuh; Matsuda, Ryotaro; Sato, Hiroshi; Kitagawa, Susumu; Sugimoto, Kunihisa; Inubushi, Yasutaka; Kubo, Kazuya; Nakamura, Takayoshi
2015-01-01
The design of inexpensive and less toxic porous coordination polymers (PCPs) that show selective adsorption or high adsorption capacity is a critical issue in research on applicable porous materials. Although use of Group II magnesium(II) and calcium(II) ions as building blocks could provide cheaper materials and lead to enhanced biocompatibility, examples of magnesium(II) and calcium(II) PCPs are extremely limited compared with commonly used transition metal ones, because neutral bridging ligands have not been available for magnesium(II) and calcium(II) ions. Here we report a rationally designed neutral and charge-polarized bridging ligand as a new partner for magnesium(II) and calcium(II) ions. The three-dimensional magnesium(II) and calcium(II) PCPs synthesized using such a neutral ligand are stable and show selective adsorption and separation of carbon dioxide over methane at ambient temperature. This synthetic approach allows the structural diversification of Group II magnesium(II) and calcium(II) PCPs.
An unusual 3D coordination polymer based on bridging interactions of the nucleobase adenine.
García-Terán, Juan P; Castillo, Oscar; Luque, Antonio; García-Couceiro, Urko; Román, Pascual; Lezama, Luis
2004-07-26
The first 3D coordination polymer containing a nucleobase as a bridging ligand, [[Cu2(mu-ade)4(H2O)2][Cu(ox)(H2O)]2 x approximately 14H2O]n (1), has been synthesized by reaction of adenine (Hade) with a basic solution of K2[Cu(ox)2] x 2H2O (ox = oxalato dianion). Compound 1 crystallizes in the trigonal space group R3 with a = b = 31.350(1) angstroms, c = 14.285(1) angstroms, V = 12158.7(10) angstroms3, and Z = 9. X-ray analysis shows a covalent 3D network in which the copper(II) centers are bridged by tridentate mu-N3,N7,N9 adeninate ligands. The compound has relatively large, nanometer-sized tubes associated with the self-assembly process directed solely by metal-ligand interactions. The covalent 3D framework remains intact upon removal of the guest water molecules trapped in the nanotubes. Magnetic measurements indicate an overall antiferromagnetic behavior of the compound. PMID:15257577
Porous coordination polymers with ubiquitous and biocompatible metals and a neutral bridging ligand.
Noro, Shin-ichiro; Mizutani, Junya; Hijikata, Yuh; Matsuda, Ryotaro; Sato, Hiroshi; Kitagawa, Susumu; Sugimoto, Kunihisa; Inubushi, Yasutaka; Kubo, Kazuya; Nakamura, Takayoshi
2015-01-01
The design of inexpensive and less toxic porous coordination polymers (PCPs) that show selective adsorption or high adsorption capacity is a critical issue in research on applicable porous materials. Although use of Group II magnesium(II) and calcium(II) ions as building blocks could provide cheaper materials and lead to enhanced biocompatibility, examples of magnesium(II) and calcium(II) PCPs are extremely limited compared with commonly used transition metal ones, because neutral bridging ligands have not been available for magnesium(II) and calcium(II) ions. Here we report a rationally designed neutral and charge-polarized bridging ligand as a new partner for magnesium(II) and calcium(II) ions. The three-dimensional magnesium(II) and calcium(II) PCPs synthesized using such a neutral ligand are stable and show selective adsorption and separation of carbon dioxide over methane at ambient temperature. This synthetic approach allows the structural diversification of Group II magnesium(II) and calcium(II) PCPs. PMID:25592677
Filling pore space in a microporous coordination polymer to improve methane storage performance.
Tran, Ly D; Feldblyum, Jeremy I; Wong-Foy, Antek G; Matzger, Adam J
2015-02-24
A strategy that allows the tuning of pore size in microporous coordination polymers (MCPs) through modification of their organic linkers is presented. When large substituents are introduced onto the linker, these pendent groups partially occupy the pores, thus reducing pore size while serving as additional adsorption sites for gases. The approach takes advantage of the fact that, for methane storage materials, small pores (0.4-0.8 nm in diameter) are more desirable than large pores since small pores promote optimal volumetric capacity. This method was demonstrated with IRMOF-8, a MCP constructed from Zn4O metal clusters and 2,6-naphthalenedicarboxylate (NDC) linkers. The NDC was functionalized through the addition of substituents including tert-butylethynyl or phenylethynyl groups. High pressure methane uptake demonstrates that the IRMOF-8 derivatives have significantly better performance than the unfunctionalized material in terms of both excess volumetric uptake and deliverable capacity. Moreover, IRMOF-8 derivatives also give rise to stronger interactions with methane molecules as shown by higher heat of adsorption values. PMID:25621891
Synthesis, structure and properties of a fumarate bridged Ni(II) coordination polymer
NASA Astrophysics Data System (ADS)
Bora, Sanchay J.; Das, Birinchi K.
2011-07-01
A 1-D coordination polymer catena[?-fumaratobis(4-cyanopyridine)diaquanickel(II)],[Ni(? -C 4H 2O 4)(4-CNpy) 2(H 2O) 2] n1 has been synthesized and structurally characterized. Compound 1 is monoclinic, P2 1/ c with unit cell parameters a = 8.8759(9) Å, b = 11.4112(11) Å, c = 8.8908(9) Å, ? = 106.010(6)°, V = 865.6(1) Å 3, Z = 2 and D calc. = 1.600 g cm -3. The structure refined to R1 = 0.0245, wR2 = 0.0626 for all 2014 unique reflections and 152 parameters; GooF = 1.056. It consists of a polymeric chain of nearly octahedral Ni 2+ centers bridged by bidentate fumarato ligands. Non-covalent interactions lead these chains to aggregate into an interesting metallosupramolecular assembly. Indexed PXRD pattern, solid state UV-vis-NIR spectral data, thermogravimetric behavior and variable temperature magnetic susceptibility data on 1 are presented.
Natural gas purification using a porous coordination polymer with water and chemical stability.
Duan, Jingui; Jin, Wanqin; Krishna, Rajamani
2015-05-01
Porous coordination polymers (PCPs), constructed by bridging the metals or clusters and organic linkers, can provide a functional pore environment for gas storage and separation. But the rational design for identifying PCPs with high efficiency and low energy cost remains a challenge. Here, we demonstrate a new PCP, [(Cu4Cl)(BTBA)8·(CH3)2NH2)·(H2O)12]·xGuest (PCP-33?guest), which shows high potential for purification of natural gas, separation of C2H2/CO2 mixtures, and selective removal of C2H2 from C2H2/C2H4 mixtures at ambient temperature. The lower binding energy of the framework toward these light hydrocarbons indicates the reduced net costs for material regeneration, and meanwhile, the good water and chemical stability of it, in particular at pH = 2 and 60 °C, shows high potential usage under some harsh conditions. In addition, the adsorption process and effective site for separation was unravelled by in situ infrared spectroscopy studies. PMID:25884592
Liu, Demin; Poon, Christopher; Lu, Kuangda; He, Chunbai; Lin, Wenbin
2014-01-01
Nanoscale coordination polymers (NCPs) are self-assembled from metal ions and organic bridging ligands, and can overcome many drawbacks of existing drug delivery systems by virtue of tunable compositions, sizes, and shapes; high drug loadings; ease of surface modification; and intrinsic biodegradability. Here we report the self-assembly of zinc bisphosphonate NCPs that carry 48±3 wt% cisplatin prodrug and 45±5 wt% oxaliplatin prodrug. In vivo pharmacokinetic studies in mice show minimal uptake of pegylated NCPs by the mononuclear phagocyte system and excellent blood circulation half-lives of 16.4±2.9 and 12.0±3.9 h for the NCPs carrying cisplatin and oxaliplatin, respectively. In all tumor xenograft models evaluated, including CT26 colon cancer, H460 lung cancer, and AsPC-1 pancreatic cancer, pegylated NCPs show superior potency and efficacy compared to free drugs. As the first example of using NCPs as nanotherapeutics with enhanced antitumor activities, this study establishes NCPs as a promising drug delivery platform for cancer therapy. PMID:24964370
Du, Zi-Yi; Xu, Ting-Ting; Huang, Bo; Su, Yu-Jun; Xue, Wei; He, Chun-Ting; Zhang, Wei-Xiong; Chen, Xiao-Ming
2015-01-12
A new perovskite-like coordination polymer [(CH3)2NH2][Cd(N3)3] is reported which undergoes a reversible ferroelastic phase transition. This transition is due to varied modes of motion of the [(CH3)2NH2](+) guest accompanied by a synergistic deformation of the [Cd(N3)3](-) framework. The unusual two-staged switchable dielectric relaxation reveals the molecular dynamics of the polar cation guest, which are well controlled by the variable confined space of the host framework. As the material switches from the ferroelastic phase to the paraelastic phase, a remarkable increase of the rotational energy barrier is detected. As a result, upon heating at low temperature, this compound shows a notable change from a low to a high dielectric state in the ferroelastic phase. This thermoresponsive host-guest system may serve as a model compound for the development of sensitive thermoresponsive dielectric materials and may be key to understanding and modulating molecular/ionic dynamics of guest molecules in confined space. PMID:25430633
Sen, Susan; Neogi, Subhadip; Aijaz, Arshad; Xu, Qiang; Bharadwaj, Parimal K
2014-04-28
In an effort towards the rational design of porous MOFs with a functionalized channel surface, 3,3',5,5'-tetracarboxydiphenylmethane (H4L1) has been used in combination with two different bipyridine ligands of similar lengths as linkers, and Zn(II) ions as nodes. Under solvothermal conditions, two Zn(II) coordination polymers, {[Zn(H2L1)(L2)] · DMF · 2H2O}n (1) and {[Zn2(L1)(L3)(DMF)2] · DMF · 4H2O}n (2) (DMF = dimethyl formamide, L2 = 3,6-di-pyridin-4-yl-[1,2,4,5]tetrazine, L3 = 4,4'-bispyridylphenyl) are formed in moderate yields. The obvious kink in the central methylene spacer of H4L1 induces either C2v or Cs symmetry in the ligand, allowing different architectures in the resulting frameworks. Single crystal X-ray analysis shows that compound 1 is a one-dimensional (1D) double chain architecture with rhombus voids, linked by Zn2(CO2)4 paddle-wheel secondary building units (SBUs). The tetrazine and pyridine moieties of the co-ligand and free carboxylic acid groups are lined along the voids of the framework. Compound 2, on the other hand, crystallizes as an infinite two-dimensional corrugated sheet structure, where individual sheets are stacked in--ABAB--patterns along the crystallographic b-axis. Thermogravimetric analysis (TGA) and variable temperature powder X-ray diffraction (VTPXRD) studies reveal high thermal stability for 1 but 2 collapses soon after desolvation. The desolvated framework 1' shows selective CO2 adsorption over N2, H2, and CH4 at 273 K, with an isosteric heat of CO2 adsorption of 21.3 kJ mol(-1), suggesting an interaction of the CO2 molecules with the channel walls. PMID:24522488
Exact canonically conjugate momenta approach to a one-dimensional neutron-proton system, I
Seiya Nishiyama; Joao da Providencia
2015-06-29
Introducing collective variables, a collective description of nuclear surface oscillations has been developed with the first quantized language, contrary to the second quantized one in Sunakawa's approach for a Bose system. It overcomes difficulties remaining in the traditional theories of nuclear collective motions: Collective momenta are not exact canonically conjugate to collective coordinates and are not independent. On the contrary to such a description, Tomonaga first gave the basic idea to approach elementary excitations in a one-dimensional Fermi system. The Sunakawa's approach for a Fermi system is also expected to work well for such a problem. In this paper, on the $isospin$ space, we define a density operator and further following Tomonaga, introduce a collective momentum. We propose an $exact$ canonically momenta approach to a one-dimensional neutron-proton (N-P) system under the use of the Grassmann variables.
Normal and generalized Bose condensation in traps: One dimensional examples
Andras Suto
2003-01-01
We prove the following results. (i) One-dimensional Bose gases which interact\\u000avia unscaled integrable pair interactions and are confined in an external\\u000apotential increasing faster than quadratically undergo a complete generalized\\u000aBose-Einstein condensation (BEC) at any temperature, in the sense that a\\u000amacroscopic number of particles are distributed on a o(N)number of one-particle\\u000astates. (ii) In a one dimensional harmonic
Normal Forms of One-Dimensional Quasihomogeneous Complete Intersections
NASA Astrophysics Data System (ADS)
Aleksandrov, A. G.
1983-02-01
In this paper the author presents an approach to the problem of classifying quasihomogeneous singularities, based on the use of simple properties of deformation theories of such singularities. By means of Grothendieck local duality the Poincaré series of the space of the first cotangent functor T' of a one-dimensional singularity is computed. Lists of normal forms and monomial bases of the spaces of T' are given for one-dimensional quasihomogeneous complete intersections with inner modality 0 and 1, and also with Milnor number less than seventeen. An adjacency diagram is constructed for all singularities that have been found. Bibliography: 33 titles.
Ghasempour, Hosein; Azhdari Tehrani, Alireza; Morsali, Ali
2015-11-01
Two new Hg(II) coordination polymers containing N,N'-Bis-pyridin-3-ylmethylene-naphtalene-1,5-diamine ligand were synthesized by conventional and sonochemical methods, characterized by spectroscopic techniques (FT-IR and elemental analysis), and their X-ray crystallographic structures were determined. The crystal packing and supramolecular features of these coordination polymers were studied using geometrical analysis and Hirshfeld surface analysis. The crystal structure analysis revealed that H?H contacts, C-H?? and C-H?X (X=Cl for 1 and X=Br for 2) hydrogen bonding interactions are strong enough to govern the supramolecular architecture. The BFDH analysis helps us to compare the predicted morphology to that obtained under ultrasonication. This study may provide further insight into discovering the role of weak intermolecular interactions in the context of nano-supramolecular assembly. PMID:26186872
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.
Chang, Xin-Hong; Qin, Jian-Hua [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Ma, Lu-Fang, E-mail: mazhuxp@126.com [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Wang, Li-Ya, E-mail: wlya@lynu.edu.cn [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); College of Chemistry and Pharmaceutical Engineering, Nanyang Normal University, Nanyang 473061 (China)
2014-04-01
Three Cu{sup II} coordination polymers, ([Cu{sub 2}(CH{sub 3}O-ip){sub 2}(bmib)]){sub n} (1), ([Cu{sub 2}(CH{sub 3}O-ip){sub 2}(bmib){sub 2}]){sub n} (2) and ([Cu(CH{sub 3}O-ip)(bbip)]?2H{sub 2}O){sub n} (3) (CH{sub 3}O-H{sub 2}ip is 5-methoxyisophthalic acid, bmib is 1,4-bis(2-methylimidazol-1-yl)butane and bbip is 1,3-bis(1H-benzimidazolyl)propane), have been synthesized by hydrothermal methods. Complexes 1–3 were structurally characterized by elemental analysis, infrared (IR) spectra and X-ray single-crystal diffraction. Complex 1 shows a 3D six-connected self-penetrating network based on paddlewheel secondary building units. Complex 2 has a 3-fold interpenetrating 3D diamond framework. Complex 3 possesses a 1D tube-like chain. Thermo-gravimetric and magnetic properties of 1–3 were also investigated. - Graphical abstract: Structures and magnetic properties of copper(II) coordination polymers constructed from 5-methoxyisophthalate linker and two flexible N-donor ancillary ligands. Three copper(II) coordination polymers with 5-methoxyisophthalate and two related flexible N-donor ancillary ligands have been synthesized and structurally characterized. Moreover, thermal behaviors and magnetic properties of these complexes have also been investigated. - Highlights: • Three Cu(II) coordination polymers were synthesized. • The conformations of N-donor ligands and pH value have an effect on the final structures. • The magnetic properties of 1–3 have been investigated.
Zhou, Bo, E-mail: zhoubo@njnu.edu.cn [Jiangsu Key Laboratory of New Power Batteries, Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biomedical Materials, College of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023 (China); Liang, Li-Mei [Jiangsu Key Laboratory of New Power Batteries, Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biomedical Materials, College of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023 (China); Yao, Jie [Analytical and Testing Center of Nanjing Normal University (China)
2014-07-01
This work concerns the isomorphous substitution of coordination polymers (CPs) and its effect on the optical and electrochemical properties. The application of CPs in electrochemical sensing was studied as well. Isomorphous coordination polymers, [Co{sub x}Zn{sub 1?x}tyr]{sub n} (tyr=L-tyrosine), where x (0–1) was controlled by the Co/Zn ratios of raw materials, were successfully synthesized via a hydrothermal method, as proved by XRD and EDS results. Their UV–vis DRS and fluorescence spectra change gradually along with the composition. Cyclic voltammograms of modified electrodes, [Co{sub x}Zn{sub 1?x}tyr]{sub n}/GCE, show that as more and more Zn replaced Co, the current signal decreases greatly and the potential shifts negatively. Much attention was paid to [Cotyr]{sub n} due to its highest sensitivity. Refreshable modified carbon paste electrode, [Cotyr]{sub n}-CPE, was used to determine nitrite, and showed pretty good performance as evidenced by chronoamperometry. The response was made very fast within mere 5 s. The linear detection range was from 5.00×10{sup ?5} to 3.45×10{sup ?3} M, with sensitivity of 263.4 mA mol{sup ?1} L cm{sup ?2}. The detection limit was found to be 2.00×10{sup ?5} M. The sensor also showed good antiinterference and reproducibility. - Graphical abstract: Evolution of the optical and electrochemical properties of isomorphic coordination polymers [Co{sub x}Zn{sub 1?x}tyr]{sub n} along with the changing of x was studied. The CP also showed perfect performance in the electrochemical determination of nitrite. - Highlights: • Isomorphous substitution of coordination polymers (CPs). • Substitution-caused evolution of optical and electrochemical properties of CPs. • Application of CPs in electrochemical sensing, an incipient area. • Perfect performance of CPs in electrochemical determination of nitrite.
Kanoo, Prakash; Matsuda, Ryotaro; Sato, Hiroshi; Li, Liangchun; Jeon, Hyung Joon; Kitagawa, Susumu
2013-10-01
Herein, we report new porous coordination polymers (PCPs) via a facile synthetic approach called "in situ generation of functionality in the ligand". Upon a synthetic process of PCPs, a neutral (-CH2OH) or a cationic functionality (-CH2-[4,4'-bipyridine](+)) was generated on a isophthalate ligand from a reactive haloalkane (-CH2Br) moiety, affording two new PCPs. The PCPs have two-dimensional layered structures with large potential solvent-accessible voids for CO2 adsorption. PMID:24016100
DOI: 10.1002/ejic.200700807 Coordination Polymers Constructed from [Mn(N)(CN)4]2
Gao, Song
of coordination polymers with the general formula [MII {CrV (N)(CN)4}]·MeCN (MII = Cr, Mn, V, Fe, Co, Ni, V) using.0 K and [MII {CrV (N)(CN)4}]·MeCN (M = Cr, Mn, Fe, Co and Ni) are weak ferromagnets (canted the synthesis of the high-valent cyanido nitrido complexes [MV (N)(CN)x]2x (M = Cr, Mn; x = 4, 5),[3,4] which
Structure Determination of the One-Dimensional Compound Sr3ZnPtO6, Containing Zinc in a
zur Loye, Hans-Conrad
Structure Determination of the One-Dimensional Compound Sr3ZnPtO6, Containing Zinc in a HighlyVember 9, 1995 We report the synthesis and structure of a new zinc-containing strontium platinum oxide, Sr3ZnPtO6, in which zinc is present in a highly unusual trigonal prismatic coordination environment
Gao, Song
Peculiar Magnetic Transition Behaviour Around 208 K in One-dimensional Nickel(III) Chain Complex [1 space group P21=c at room temperature.7 The coordination geometry of the nickel atom in the [Ni(mnt)2]À between two positions about 1.63 #A apart, and one of which is modeled at 50% occupancy. The benzene ring
NASA Astrophysics Data System (ADS)
Zhang, Guoqi; Wang, Qian; Qian, Yan; Yang, Guoqiang; Shi Ma, Jin
2006-08-01
The 3D open framework coordination polymers, [Eu 2( fum) 3(H 2O) 4] n·3 nH 2O ( 1, fum=fumaric acid) and [Eu( pdc)(H pdc)] n ( 2, pdc=pyridine-2,5-dicarboxylic acid) have been synthesized via hydrothermal procedure. Their molecular structures were determined by single-crystal X-ray diffraction analysis. Polymer 1 adopts a 3D microporous structure filled with disordered free water molecules which interact by hydrogen bonds with terminal water bound to the metal centers. IR spectroscopy, TGA and powder X-ray diffraction analysis revealed that the remarkable dehydration-rehydration process of open-framework 1 is completely reversible. Polymer 2 forms a 3D framework composed of 2D grid-like inorganic subnetworks and pdc ligands as linkers. This solid is highly stable up to 405 °C. The solid-state photoluminescence measurements exhibited red light-emitting characteristic of two europium(III) coordination polymers. Moreover, the anhydrous products were found to be more strongly fluorescent and be of longer lifetime.
NASA Astrophysics Data System (ADS)
Sabounchei, Seyyed Javad; Bagherjeri, Fateme Akhlaghi; Boskovic, Colette; Gable, Robert W.
2013-08-01
Protonated sulfonium ylide chlorocadmate compounds of type [(Me)2SCHC(O)CHR]+[CdCl]-(R = H(1); p-Br (2); p-Me (3); p-OMe (4); p-NO2 (5)) were prepared by the reaction of ?-keto stabilized sulfonium ylides (Me)2SCHC(O)C6H4R with CdCl2?H2O in 1:2 M ratios using methanol as solvent. Characterization of the compounds by IR, 1H- and 13C NMR spectroscopy indicated the absence of coordination of the protonated sulfonium ylide to the metal through either the carbon or oxygen atoms. The crystal structures of compounds 1 and 2 were both found to consist of organic cations, [(Me)2SCHC(O)CHR]+(R = H(1) and p-Br (2)) and infinite one-dimensional chains of formula [CdCl]n- In both structures each Cd atom is five-coordinate with square pyramidal coordination geometry.
Makida, Hiroki; Abe, Hajime; Inouye, Masahiko
2015-02-14
An amphiphilic meta-ethynylpyridine polymer with chiral amide side chains was developed. The polymer was prepared by sequential Sonogashira reactions, and the product was soluble in polar and apolar solvents. The additive effects of metal salts on the polymer were examined in water and aqueous EtOH on the basis of UV-vis and CD spectra. The enhancement of the positive Cotton effect and hypochromism around 360 nm occurred by the addition of various metal salts, indicating the coordination of the cations to the amide side chains of the polymer to stabilise the helical structure. Among them, rare-earth metal salts, especially Sc(OTf)3 showed more efficient additive effects probably because of its strong coordination ability even in water. Positive cooperativity was observed for the coordination of Sc(OTf)3 to the polymer in aqueous EtOH. PMID:25473810
Spin Correlation Effects In a One Dimensional Electron Gas
Murat Tas; Mehmet Tomak
2001-01-01
The Singwi, Sjolander, Tosi, Land (SSTL) approach is generalized to study the spin correlation effects in a one dimensional electron gas. It is shown that the SSTL approach is capable of generating results comparable to the more widely used STLS approach.
One-Dimensional NOE Experiments Using Pulsed Field Gradients
Katherine Stott; James Keeler; Que N. Van; A. J. Shaka
1997-01-01
Previously, it has been shown that the use of pulsed field gradients in one-dimensional NOE experiments results in spectra of much higher quality than it has previously been possible to record. Such high-quality spectra make it possible to measure, with complete confidence, very small NOE enhancements and also make it straightforward to measure NOE buildup curves. In this paper, the
Effect of Hund coupling on one-dimensional Luttinger liquids
NASA Astrophysics Data System (ADS)
Lee, H. C.; Eric Yang, S.-R.
2000-07-01
Two one-dimensional Luttinger liquid systems coupled by Hund coupling are studied by the renormalization-group and non-Abelian bosonization methods. It is found that the Hund coupling is always relevant irrespective of the repulsive interaction between electrons within each chain. The properties of the resulting strong coupling fixed point are discussed.
Optimal One-Dimensional Relay Placement in Cognitive Radio Networks
Huang, Jianwei
Optimal One-Dimensional Relay Placement in Cognitive Radio Networks Junhua Zhu and Jianwei Huang for a secondary user in a cognitive radio network subject to outage constraints. With selection decode the approximation instead to solve the relay placement problem in cognitive radio networks. We find that the optimal
Transition density of one-dimensional diffusion with discontinuous drift
NASA Technical Reports Server (NTRS)
Zhang, Weijian
1990-01-01
The transition density of a one-dimensional diffusion process with a discontinuous drift coefficient is studied. A probabilistic representation of the transition density is given, illustrating the close connections between discontinuities of the drift and Brownian local times. In addition, some explicit results are obtained based on the trivariate density of Brownian motion, its occupation, and local times.
Fusion for the one-dimensional Hubbard model
Niklas Beisert; Marius de Leeuw; Panchali Nag
2015-03-16
We discuss a formulation of the fusion procedure for integrable models which is suitable for application to non-standard R-matrices. It allows for construction of bound state R-matrices for AdS/CFT worldsheet scattering or equivalently for the one-dimensional Hubbard model. We also discuss some peculiar cases that arise in these models.
One-Dimensional Model for Pulverized Coal Combustion and Gasification
PHILIP J. SMITH; L. DOUGLAS SMOOT
1980-01-01
A one-dimensional model has been developed for pulverized coal combustors and gasifiers. The model describes the response of a coal particle system to its thermal, chemical and physical environment. Moisture vaporization, coal devolatilization, heterogeneous char oxidation, gas particle interchange, radiation, gas phase oxidation, primary and secondary stream mixing, and heat losses are considered. A predictor-corrector solution technique was used to
Structural Reliability Analysis for One Dimensional, Two Phase Miscible Flow
New York at Stoney Brook, State University of
Structural Reliability Analysis for One Dimensional, Two Phase Miscible Flow David A. Coker3600 December 22, 1992 Abstract An analytic structural reliability analysis is performed for first contact mis and the permeability of the medium. First order analysis is essentially exact for the normal--normal model
Coupled optical microcavities in one-dimensional photonic bandgap structures
Mehmet Bayindir; C. Kural; E. Ozbay
2001-01-01
We present a detailed theoretical and experimental study of the evanescent coupled optical microcavity modes in one-dimensional photonic bandgap structures. The coupled-cavity samples are fabricated by depositing alternating hydrogenated amorphous silicon nitride and silicon oxide layers. Splitting of the eigenmodes and formation of a defect band due to interaction between the neighbouring localized cavity modes are experimentally observed. Corresponding field
Quasistationary distributions for one-dimensional diffusions with killing
David Steinsaltz; Steven N. Evans
2004-01-01
We extend some results on the convergence of one-dimensional diffusions killed at the boundary, conditioned on extended survival, to the case of general killing on the interior. We show, under fairly general conditions, that a diffusion conditioned on long survival either runs off to infinity almost surely, or almost surely converges to a quasistationary distribution given by the lowest eigenfunction
Thermal and Electrical Transport Study of One Dimensional Nanomaterials
Yin, Liang
2013-07-13
contribution due to scattering at the wire boundaries. Three one-dimensional nanostructured thermoelectric candidates - SiGe nanowires, SrTiO3 nanowires, and ZnO nanowires – were presented and discussed in this dissertation. SiGe nanowires are successfully...
One-Dimensional Thermomechanical Constitutive Relations for Shape Memory Materials
C. Liang; C. A. Rogers
1990-01-01
The use of the thermoelastic martensitic transformation and its reverse transformation has recently been proposed and demonstrated for several active control ap plications. However, the present constitutive models have lacked several important funda mental concepts that are essential for many of the proposed intelligent material system ap plications such as shape memory hybrid composites.A complete, unified, one-dimensional constitutive model of
Asymptotical analysis of one dimensional gas dynamics equations
A. Krylovas; R. ?iegis
2001-01-01
A method of averaging is developed for constructing a uniformly valid asymptotic solution for weakly nonlinear one dimensional gas dynamics systems. Using this method we give the averaged system, which disintegrates into independent equations for the non?resonance systems. Conditions of the resonance for periodic and almost periodic solutions are presented. In the resonance case the averaged system is solved numerically.
Photonic dispersion relation in a one-dimensional quasicrystal
Toshiaki Hattori; Noriaki Tsurumachi; Sakae Kawato; Hiroki Nakatsuka
1994-01-01
The dispersion relation of photons transmitting through a photonic one-dimensional quasicrystal arranged in a Fibonacci sequence was observed by measuring the spectrum of the phase change of the transmitted light using a Michelson-type interferometer. The phase spectrum obtained clearly showed the self-similar structure characteristic to dispersion curves of Fibonacci lattices.
ACOUSTIC WAVE TRAPPING IN ONE-DIMENSIONAL AXISYMMETRIC ARRAYS
ACOUSTIC WAVE TRAPPING IN ONE- DIMENSIONAL AXISYMMETRIC ARRAYS by M. MCIVER (Department 2011. Revise 2011] Summary The existence of acoustic, Rayleigh-Bloch modes in the vicinity of a one for the acoustic wave-field in the neighbourhood of such an array is obtained and solved with the use of a Galerkin
Toward precise solution of one-dimensional velocity inverse problems
Gray, S.; Hagin, F.
1980-01-01
A family of one-dimensional inverse problems are considered with the goal of reconstructing velocity profiles to reasonably high accuracy. The travel-time variable change is used together with an iteration scheme to produce an effective algorithm for computation. Under modest assumptions the scheme is shown to be convergent.
Appropriateness of one-dimensional calculations for repository analysis
Eaton, R.R.
1994-01-01
This paper brings into focus the results of numerous studies that have addressed issues associated with the validity of assumptions which are used to justify reducing the dimensionality of numerical calculations of water flow through Yucca Mountain, NV. It is shown that in many cases, one-dimensional modeling is more rigorous than previously assumed.
Asymptotic velocity of one dimensional diffusions with periodic drift
P. Collet S. Martinez
2007-05-10
We consider the asymptotic behaviour of the solution of one dimensional stochastic differential equations and Langevin equations in periodic backgrounds with zero average. We prove that in several such models, there is generically a non vanishing asymptotic velocity, despite of the fact that the average of the background is zero.
DEFINABLE STRUCTURES IN O-MINIMAL THEORIES: ONE DIMENSIONAL TYPES
Peterzil, Ya'acov
DEFINABLE STRUCTURES IN O-MINIMAL THEORIES: ONE DIMENSIONAL TYPES ASSAF HASSON , ALF ONSHUUS of Zilber's trichotomy: Theorem 1. Let N be a stable structure definable in an o-minimal structure M. If dim): Theorem 2. Let M be an o-minimal structure and N definable in M. Let p SN (N) be one-M-dimensional
NUMERICAL CALCULATION OF PRECURSOR FIELDS IN ONE DIMENSIONAL PHOTONIC CRYSTAL
Reza Safian; Costas D. Sarris; Mohammad Mojahedi
The presence of superluminal (in excess of the speed of light in vacuum) or negative group velocities in passive or active Lorentzian medium, one-dimensional photonic crys- tal (1DPC), undersized waveguide, and other structures has been theoretically predicted and experimentally observed. While due to the temporal or structural dispersions the group velocity in these media is abnormal, it has been ar-
One-Dimensional Ising Model with "k"-Spin Interactions
ERIC Educational Resources Information Center
Fan, Yale
2011-01-01
We examine a generalization of the one-dimensional Ising model involving interactions among neighbourhoods of "k" adjacent spins. The model is solved by exploiting a connection to an interesting computational problem that we call ""k"-SAT on a ring", and is shown to be equivalent to the nearest-neighbour Ising model in the absence of an external…
High energy eigenfunctions of one-dimensional Schrödinger ...
1910-71-00
Mar 8, 2007 ... For a class of one-dimensional Schrödinger operators with polyno- mial potentials that .... Theorem A. The spectrum of the problem (4), (5) is discrete, and to each eigenvalue .... (?1)l(it)ddt = 0} that is ? = ? ?. 2. + ?(l + 2k) d + 2.
One-Dimensional Helical Transport in Topological Insulator Nanowire Interferometers
Cui, Yi
One-Dimensional Helical Transport in Topological Insulator Nanowire Interferometers Seung Sae Hong to both physics and device applications of topological insulators. Topological insulator nanowires an observation of a topologically protected 1D mode of surface electrons in topological insulator nanowires
One-dimensional quantum walks with absorbing boundaries
Eric Bach; Susan Coppersmith; Marcel Paz Goldschen; Robert Joynt; John Watrous
2002-01-01
In this paper we analyze the behavior of quantum random walks. In particular we present several new results for the absorption probabilities in systems with both one and two absorbing walls for the one-dimensional case. We compute these probabilites both by employing generating functions and by use of an eigenfunction approach. The generating function method is used to determine some
One-dimensional quantum walks with absorbing boundaries
Eric Bach; Susan Coppersmith; Marcel Paz Goldschen; Robert Joynt; John Watrous
2004-01-01
In this paper we analyze the behavior of quantum random walks. In particular we present several new results for the absorption probabilities in systems with both one and two absorbing walls for the one-dimensional case. We compute these probabilities both by employing generating functions and by use of an eigenfunction approach. The generating function method is used to determine some
Energy transport in one-dimensional thermoelectric systems
K. A. Chao; Magnus Larsson
2006-01-01
The efficiency of thermoelectric power generators and the coefficient of performance of thermoelectric refrigerators increase rapidly in the region of small ZT, and then level off to a flat curve in the region of large ZT, where ZT is the figure of merit. Therefore, simply because one-dimensional thermoelectric materials have high ZT predicted theoretically does not imply that efficient thermoelectric
Ground State Entanglement in One Dimensional Translationally Invariant Quantum Systems
Irani, Sandy
Ground State Entanglement in One Dimensional Translationally Invariant Quantum Systems Sandy Irani {Hn} for the infinite chain. The spectral gap of Hn is (1/poly(n)). Moreover, for any state in the ground space of Hn and any m, there are regions of size m with entanglement entropy (min{m, n
On condensation of a one-dimensional nonideal Boson gas
NASA Astrophysics Data System (ADS)
Papoyan, Vl. V.; Zagrebnov, V. A.
1985-11-01
We report the properties of a one-dimensional model which exhibits Bose-Einstein condensation. The problem of canonical and grand canonical ensemble equivalence is considered. A strong equivalence is shown to be connected with uniqueness of the limiting Gibbs states.
Approximate Approaches to the One-Dimensional Finite Potential Well
ERIC Educational Resources Information Center
Singh, Shilpi; Pathak, Praveen; Singh, Vijay A.
2011-01-01
The one-dimensional finite well is a textbook problem. We propose approximate approaches to obtain the energy levels of the well. The finite well is also encountered in semiconductor heterostructures where the carrier mass inside the well (m[subscript i]) is taken to be distinct from mass outside (m[subscript o]). A relevant parameter is the mass…
Parameter Identification in One-Dimensional Partial Differential Algebraic Equations
Schittkowski, Klaus
optimization,partial differential algebraic equations, method of lines 1 Department of Computer Science), for example. The system of partial differential algebraic equations (PDAEs) is discretized by the methodParameter Identification in One-Dimensional Partial Differential Algebraic Equations K
Ji-Hua Deng; Xiao-Lin Yuan; Guang-Quan Mei
2010-01-01
1,4-benzeneditetrazolate [H2BDT] (1) and its 3D coordination polymer [Zn(BDT)]n (2), have been synthesized and structurally characterized by infrared spectroscopy (IR), thermal gravimetric analysis (TG), and single-crystal\\/powder X-ray diffraction. The result of the single-crystal X-ray diffraction analysis indicates that 1 is a 3D supramolecular structure stabilized by intermolecular hydrogen bonds and ?…? stacking interactions. 2 is a 3D (4,4)-connected coordination polymer
Shi-Yuan Zhang; Zhen-Jie Zhang; Wei Shi; Bin Zhao; Peng Cheng
2010-01-01
Two new Co(II) coordination polymers with mixed ligands, {[Co(BTA)0.5(DBI)2]·DBI·H2O}n (1) and [Co(PDA)(DBI)(H2O)]n (2) (H4BTA=benzene-1,2,4,5-tetracarboxylic acid; H2PDA=2,2?-(1,2-phenylene)diacetic acid; DBI=5,6-dimethyl-1H-benzoimidazole) have been synthesized under hydrothermal conditions, respectively. Both of them are characterized by elemental analyses, powder X-ray diffraction, thermogravimetric analysis, single-crystal X-ray diffraction, and magnetic susceptibilities. In 1, the Co(II) ions are four-coordinated and lie in distorted tetrahedron coordination environment. 1D ladder-like
Synthesis, crystal structures and thermal properties of new copper(I) halide coordination polymers
NASA Astrophysics Data System (ADS)
Näther, Christian; Greve, Jan; Jeß, Inke
2002-05-01
The new copper(I) halide coordination polymers {3}/{?}poly[CuCl( ?-2,5-dimethylpyrazine-N,N')] ( I), {2}/{?}poly[CuBr( ?-2,5-dimethylpyrazine-N,N')] ( II) and {2}/{?}poly[Cu 2X 2( ?-2,5-dimethylpyrazine-N,N')] (X=Br ( III), I ( IV)) were synthesized by the reaction of the copper(I) halides with 2,5-dimethylpyrazine in acetonitrile. In the crystal structure of I, helical CuCl chains are found, which are connected by the 2,5-dimethylpyrazine ligands forming a three-dimensional structure. In the structure of compound II Cu 2Br 2 dimers and in compounds III and IV CuX double chains (X=Br, I) occur which are connected via the ligands to sheets. The thermal properties of all compounds were investigated using simultaneously differential thermoanalysis (DTA), thermogravimetry (TG) and mass spectroscopy (MS) as well as temperature resolved X-ray powder diffraction. On heating compound I transforms into the new compound Cu 2Cl 2(2,5-dimethylpyrazine) ( V), which forms CuCl on further heating. For compound II in the first step a transformation into the 2:1 compound III is observed, which loses again a part of the ligands forming the new copper(I) halide rich compound Cu 4Br 4(2,5-dimethylpyrazine) ( VI). A halide rich compound Cu 4I 4(2,5-dimethylpyrazine) ( VII) which is presumably isotypic to VI is also observed during the thermal decomposition of IV. On further heating both 4:1 compounds transform directly to CuBr and CuI.
Werner, Julia; Rams, Micha?; Tomkowicz, Zbigniew; Run?evski, Tom?e; Dinnebier, Robert E; Suckert, Stefan; Näther, Christian
2015-03-16
Reaction of cobalt thiocyanate with 4-acetylpyridine leads to the formation of [Co(NCS)2(4-acetylpyridine)2]n (3/I). In its crystal structure the Co cations are connected by pairs of ?-1,3-bridging thiocyanato ligands into dimers that are further connected into layers by single anionic ligands. DTA-TG measurements of Co(NCS)2(4-acetyl-pyridine)4 (1) led to the formation of 3/I. In contrast, when the hydrate Co(NCS)2(4-acetyl-pyridine)2(H2O)2 (2) is decomposed, a mixture of 3/I and a thermodynamically metastable form 3/II is obtained. Further investigations reveal that thermal annealing of 2 leads to the formation of 3/II, that contains only traces of the stable form 3/I. DSC and temperature dependent X-ray powder diffraction (XRPD) measurements prove that 3/II transforms into 3/I on heating. The crystal structure of 3/II was determined ab initio from XRPD data. In its crystal structure the Co cations are linked by pairs of bridging thiocyanato anions into a 1D coordination polymer, and thus, 3/II is an isomer of 3/I. Magnetic measurements disclose that the stable form 3/I only shows paramagnetism without any magnetic anomaly down to 2 K. In contrast, the metastable form 3/II shows ferromagnetic behavior. The phase transition into ordered state at Tc = 3.8 K was confirmed by specific heat measurements. Alternating current susceptibility measurements show frequency dependent maxima in ?' and ??, which is indicative for a slow relaxation of the magnetization. PMID:25741770
Liu, Xiangyu; Cen, Peipei; Li, Hui; Ke, Hongshan; Zhang, Sheng; Wei, Qing; Xie, Gang; Chen, Sanping; Gao, Shengli
2014-08-01
Based on the solvent-induced effect, three new azido-copper coordination polymers--[Cu(2-na)(N3)] (1), [Cu(2-na)(N3)] (2), and [Cu(2-na)(N3)(C2H5OH)] (3) (where 2-na = 2-naphthoic acid)--have been successfully prepared. Structure analysis shows that the Cu(II) cations in compounds 1-3 present tetra-, penta-, and hexa-coordination geometries, respectively. Compound 1 is a well-isolated one-dimensional (1D) chain with the EO-azido group, while 2 is an isomer of 1 and exhibits a two-dimensional (2D) layer involving the EE-azido group. Thermodynamically, density functional theory (DFT) calculation reveals that 2 occupies the stable state and 1 locates in the metastable state. Compound 3 consists of a 1D chain with triple bridging mode, which is derived from 1, and undergoes a single-crystal-to-single-crystal transformation by soaking in ethanol solvent; the powdery product of 1, namely 1b, could be yielded after the dealcoholization of compound 3. Magnetic measurements indicate that compounds 1-3 perform strong intrachain ferromagnetic interactions, experiencing long-range magnetic ordering and slow magnetic relaxation. Compound 1 features the metamagnetic behavior with a transition temperature of 15 K, while 2 and 3 display spin glass behavior with the phase transition temperatures of 15 and 12 K, respectively. Magneto-structure relationships are investigated as well. PMID:25014208
Polunin, Ruslan A; Burkovskaya, Nataliya P; Satska, Juliya A; Kolotilov, Sergey V; Kiskin, Mikhail A; Aleksandrov, Grigory G; Cador, Olivier; Ouahab, Lahcène; Eremenko, Igor L; Pavlishchuk, Vitaly V
2015-06-01
One-dimensional coordination polymer [Co(Piv)2(4-ptz)(C2H5OH)2]n (compound 1, Piv(-) = pivalate, 4-ptz = 2,4,6-tris(4-pyridyl)-1,3,5-triazine) was synthesized by interaction of Co(II) pivalate with 4-ptz. Desolvation of 1 led to formation of [Co(Piv)2(4-ptz)]n (compound 2), which adsorbed N2 and H2 at 78 K as a typical microporous sorbent. In contrast, absorption of methanol and ethanol by 2 at 295 K led to structural transformation probably connected with coordination of these alcohols to Co(II). Formation of 2 from 1 was accompanied by change of color of sample from orange to brown and more than 2-fold decrease of molar magnetic susceptibility (?M) in the temperature range from 2 to 300 K. Resolvation of 2 by ethanol or water resulted in restoration of spectral characteristics and ?M values almost to the level of that of 1. ?MT versus T curves for 1 and samples, obtained by resolvation of 2 by H2O or C2H5OH, were fitted using a model for Co(II) complex with zero-field splitting of this ion. PMID:25974728
Spinons, Solitons, and Breathers in Quasi-One-Dimensional Magnets
NASA Astrophysics Data System (ADS)
Broholm, Collin
2006-03-01
By scattering neutrons from coordination polymer magnets, we contrast the effects of a uniform and a staggered magnetic field on the quantum critical state of a spin-1/2 chain. In a partially magnetized state of copper pyrazine dinitrate (CuPzN) we find bounded spectral continua indicating that neutrons scatter from spin-1/2 quasi-particle pairs [1]. The complex boundaries including an incommensurate soft spot result from a field induced shift in the Fermi points for these quasi-particles. The measurements indicate that the magnetized state of CuPzN remains quantum critical. Copper benzoate [2] and CuCl2^.2(dimethylsulfoxide) (CDC) [3] differ from CuPzN in that there are two spins per unit cell along the spin chain. Rather than continuous spectra, we find resolution limited gapped excitations when these materials are subject to high fields. So with two spins per unit cell, an applied field can drive the spin-1/2 chain away from criticality. The explanation for this effect was provided by Affleck and Oshikawa. The alternating coordination environment induces a transverse staggered field and spinon binding. The quantum sine-Gordon model is the relevant low energy field theory and it predicts soliton and breather excitations at specific energies and wave vectors that we compare to the experiments. We shall also compare a complete measurement of the dynamic spin correlation function for CDC in a field to exact diagonalization results for a spin-1/2 chain with a staggered and uniform magnetic field [4]. [1] M. B. Stone, D. H. Reich, C. Broholm, K. Lefmann, C. Rischel, C. P. Landee, and M. M. Turnbull, Phys. Rev. Lett. 91, 037205 (2003). [2] M. Kenzelmann, Y. Chien, C. Broholm, D. H. Reich, and Y. Qiu, Phys. Rev. Lett. 93, 017204 (2004). [3] D. C. Dender, P. R. Hammar, Daniel H. Reich, C. Broholm, and G. Aeppli, Phys. Rev. Lett. 79, 1750 (1997). [4] M. Kenzelmann, C. D. Batista, Y. Chen, C. Broholm, D. H. Reich, S. Park, and Y. Qiu, Phys. Rev. B 71, 094411 (2005).
NASA Astrophysics Data System (ADS)
Yetirmishli, G. C.; Kazimova, S. E.; Kazimov, I. E.
2011-09-01
We present the method for determining the velocity model of the Earth's crust and the parameters of earthquakes in the Middle Kura Depression from the data of network telemetry in Azerbaijan. Application of this method allowed us to recalculate the main parameters of the hypocenters of the earthquake, to compute the corrections to the arrival times of P and S waves at the observation station, and to significantly improve the accuracy in determining the coordinates of the earthquakes. The model was constructed using the VELEST program, which calculates one-dimensional minimal velocity models from the travel times of seismic waves.
Quantum and Thermal Effects of Dark Solitons in a One-Dimensional Bose Gas
Martin, A. D.; Ruostekoski, J. [School of Mathematics, University of Southampton, Southampton SO17 1BJ (United Kingdom)
2010-05-14
We numerically study the imprinting and dynamics of dark solitons in a bosonic atomic gas in a tightly confined one-dimensional harmonic trap both with and without an optical lattice. Quantum and thermal fluctuations are synthesized within the truncated Wigner approximation in the quasicondensate description. We track the soliton coordinates and calculate position and velocity uncertainties. We find that the phase fluctuations lower the classically predicted soliton speed and seed instabilities. Individual runs show interactions of solitons with sound waves, splitting, and disappearing solitons.
NASA Astrophysics Data System (ADS)
Qiblawi, Sultan H.; LaDuca, Robert L.
2014-01-01
A series of layered divalent copper coordination polymers containing 1,4-cyclohexanedicarboxylate and long-spanning pyridyl-piperazine type ligands exhibits greatly different co-crystallized water molecule aggregations depending on the specific ligands used. Both [Cu(t-14cdc)(4-bpmp)]n (1, t-14cdc = trans-1,4-cyclohexanedicarboxylate, 4-bpmp = bis(4-pyridylmethyl)piperazine) and {[Cu(t-14cdc)(4-bpfp)(H2O)2]·6H2O}n (2, 4-bpfp = bis(4-pyridylformyl)piperazine) possess 2D (4,4) coordination polymer grids. However 1 lacks any co-crystallized water and has pinched grid apertures, while 2 manifests infinite water tapes with T6(2)4(2) classification and rectangular grid apertures. {[Cu2(c-14cdc)2(4-bpmp)]·2H2O}n (3, c-14cdc = cis-1,4-cyclohexanedicarboxylate) has [Cu2(c-14cdc)]2 ribbons with paddlewheel dimeric units linked into 2D slabs by 4-bpmp tethers, along with isolated water molecule pairs. In contrast, {[Cu2(c-14cdc)2(4-bpfp)]·10H2O}n (4) shows a very similar underlying coordination polymer topology but entrains unique decameric water molecule clusters. The minor product {[Cu2(c-14cdcH)2(t-1,4-cdc)(4-bpfp)2(H2O)2]·2H2O}n (5) was isolated along with 4; this compound underwent some in situ cis to trans cyclohexane-dicarboxylate ligand isomerization and exhibits a ladder polymer motif.
Liu, Jian-Jun; Li, Zuo-Yin; Yuan, Xiong; Wang, Yao; Huang, Chang-Cang
2014-06-01
The title complex, [Cu(C6H4N3)]n, was synthesized by the reaction of cupric nitrate, 1H-benzotriazole (BTAH) and aqueous ammonia under hydrothermal conditions. The asymmetric unit contains three crystallographically independent Cu(I) cations and two 1H-benzotriazolate ligands. Two of the Cu(I) cations, one with a linear two-coordinated geometry and one with a four-coordinated tetrahedral geometry, are located on sites with crystallographically imposed twofold symmetry. The third Cu(I) cation, with a planar three-coordinated geometry, is on a general position. Two Cu(I) cations are doubly bridged by two BTA(-) ligands to afford a noncentrosymmetric planar [Cu2(BTA)2] subunit, and two [Cu2(BTA)2] subunits are arranged in an antiparallel manner to form a centrosymmetric [Cu2(BTA)2]2 secondary building unit (SBU). The SBUs are connected in a crosswise manner via the sharing of four-coordinated Cu(I) cations, Cu-N bonding and bridging by two-coordinate Cu(I) cations, resulting in a one-dimensional chain along the c axis. These one-dimensional chains are further linked by C-H···? and weak van der Waals interactions to form a three-dimensional supramolecular architecture. PMID:24898965
NASA Astrophysics Data System (ADS)
Beheshti, Azizolla; Nobakht, Valiollah; Carlucci, Lucia; Proserpio, Davide M.; Abrahams, Carmel
2013-04-01
Two new coordination polymers [Cu2(?3-SCN)2(?-bbd)]n (1) and {[Cu(?-bbd)1.5](PF6)}n (2) were synthesized by the reactions of 1,4-bis(3,5-dimethylpyrazol-1-yl)butane (bbd) with the corresponding copper(I) salts, in order to evaluate the effect of the counter anion on the structure of the resulting products. The structure of these compounds were determined by X-ray crystallography; Compound 1 is a 2D coordination polymer, in which the thiocyanate ligand adopts uncommon ?3-1?1N;2:3?2S coordination mode to link three tetrahedrally coordinated copper centers. The fourth coordination site on each copper atom is occupied by a pyrazole nitrogen atom belonging to a ?-bbd ligand. In contrast to 1, 2 is a 1D chain coordination polymer in which the copper atoms, adopting a distorted trigonal planar geometry, are linked by bridging bbd ligands having alternately two different conformations. The results indicate that the use of a coordinating counter anion as thiocyanate which is capable of bridging more than one metal center instead of non-coordinating hexafluorophosphate anion, promotes the formation of a 2D polymer over a 1D polymeric chain. The complexes have also been characterized by elemental analysis, IR spectroscopy, XRPD and thermal analysis.
Quasi-one-dimensional optical lattices for soliton manipulation.
Lopez-Aguayo, Servando; Ruelas-Valdez, Cesar; Perez-Garcia, Benjamin; Ortiz-Ambriz, Antonio; Hernandez-Aranda, Raul I; Gutiérrez-Vega, Julio C
2014-11-15
Based on angular spectrum engineering, we report the generation of optical lattices whose two-dimensional transverse nondiffracting pattern can be reduced to a quasi-one-dimensional intensity structure formed by either a single or multiple parallel channels. Remarkably, many features for each channel such as its maximum intensity, modulation, width, or separation among channels, can be controlled and modified in order to meet the requirements of particular applications. In particular, we demonstrate that these lattices can provide useful schemes for soliton routing and steering. We demonstrate the existence domain of ground-state solitons for the single quasi-one-dimensional lattice, and we show that these nondiffracting beams allow "push and pull" dynamics among the neighbor solitons propagated along the nondiffracting channels generated. PMID:25490515
Thermodynamics of strongly correlated one-dimensional Bose gases
NASA Astrophysics Data System (ADS)
Vogler, Andreas; Labouvie, Ralf; Stubenrauch, Felix; Barontini, Giovanni; Guarrera, Vera; Ott, Herwig
2013-09-01
We investigate the thermodynamics of one-dimensional (1D) Bose gases in the strongly correlated regime. To this end, we prepare ensembles of independent 1D Bose gases in a two-dimensional optical lattice and perform high-resolution in situ imaging of the column-integrated density distribution. Using an inverse Abel transformation we derive effective one-dimensional line-density profiles and compare them to exact theoretical models. The high resolution allows for a direct thermometry of the trapped ensembles. The knowledge about the temperature enables us to extract thermodynamic equations of state such as the phase-space density, the entropy per particle, and the local pair-correlation function.
Excitonic condensation in spatially separated one-dimensional systems
NASA Astrophysics Data System (ADS)
Abergel, D. S. L.
2015-05-01
We show theoretically that excitons can form from spatially separated one-dimensional ground state populations of electrons and holes, and that the resulting excitons can form a quasicondensate. We describe a mean-field Bardeen-Cooper-Schrieffer theory in the low carrier density regime and then focus on the core-shell nanowire giving estimates of the size of the excitonic gap for InAs/GaSb wires and as a function of all the experimentally relevant parameters. We find that optimal conditions for pairing include small overlap of the electron and hole bands, large effective mass of the carriers, and low dielectric constant of the surrounding media. Therefore, one-dimensional systems provide an attractive platform for the experimental detection of excitonic quasicondensation in zero magnetic field.
Multiband effects in one-dimensional bosons in optical lattices
NASA Astrophysics Data System (ADS)
Xu, Wei; Rigol, Marcos
2015-03-01
We use path integral quantum Monte Carlo simulations to study multiband effects in ultracold bosons in optical lattices. We restrict our study to one-dimensional systems where, in the absence of the lattice, we recover analytic results for the Lieb-Liniger model. The latter is the model that describes one-dimensional bosons with contact interactions. We first discuss how cold finite systems need to be in order for one to observe ground state physics. We then show that, in shallow lattice potentials, higher Bloch bands lead to renormalized two-body interactions. We present a study of the phase diagram of these systems at intermediate interaction strengths in shallow lattice potentials, and report a detailed comparison with the phase diagram of the one-band Bose-Hubbard model.
Entanglement vs. gap for one-dimensional spin systems
Hastings, Matthew [Los Alamos National Laboratory; Aharonov, Dorit [HEBREW UNIV; Gottesman, Daniel [PERIMETER INSTITUTE
2008-01-01
We study the relationship between entanglement and spectral gap for local Hamiltonians in one dimension. The area law for a one-dimensional system states that for the ground state, the entanglement of any interval is upper-bounded by a constant independent of the size of the interval. However, the possible dependence of the upper bound on the spectral gap {Delta} is not known, as the best known general upper bound is asymptotically much larger than the largest possible entropy of any model system previously constructed for small {Delta}. To help resolve this asymptotic behavior, we construct a family of one-dimensional local systems for which some intervals have entanglement entropy which is polynomial in 1/{Delta}, whereas previously studied systems had the entropy of all intervals bounded by a constant times log(1/{Delta}).
One-dimensional Hubbard–Luttinger model for carbon nanotubes
NASA Astrophysics Data System (ADS)
Ishkhanyan, H. A.; Krainov, V. P.
2015-06-01
A Hubbard–Luttinger model is developed for qualitative description of one-dimensional motion of interacting Pi-conductivity-electrons in carbon single-wall nanotubes at low temperatures. The low-lying excitations in one-dimensional electron gas are described in terms of interacting bosons. The Bogolyubov transformation allows one to describe the system as an ensemble of non-interacting quasi-bosons. Operators of Fermi excitations and Green functions of fermions are introduced. The electric current is derived as a function of potential difference on the contact between a nanotube and a normal metal. Deviations from Ohm law produced by electron–electron short-range repulsion as well as by the transverse quantization in single-wall nanotubes are discussed. The results are compared with experimental data.
Entanglement vs. gap for one-dimensional spin systems
Daniel Gottesman; M. B. Hastings
2010-04-16
We study the relationship between entanglement and spectral gap for local Hamiltonians in one dimension. The area law for a one-dimensional system states that for the ground state, the entanglement of any interval is upper-bounded by a constant independent of the size of the interval. However, the possible dependence of the upper bound on the spectral gap Delta is not known, as the best known general upper bound is asymptotically much larger than the largest possible entropy of any model system previously constructed for small Delta. To help resolve this asymptotic behavior, we construct a family of one-dimensional local systems for which some intervals have entanglement entropy which is polynomial in 1/Delta, whereas previously studied systems, such as free fermion systems or systems described by conformal field theory, had the entropy of all intervals bounded by a constant times log(1/Delta).
One Dimensional Mimicking of Electronic Structure: The Case for Exponentials
Baker, Thomas E; Wagner, Lucas O; Burke, Kieron; White, Steven R
2015-01-01
An exponential interaction is constructed so that one-dimensional atoms and chains of atoms mimic the general behavior of their three-dimensional counterparts. Relative to the more commonly used soft-Coulomb interaction, the exponential greatly diminishes the computational time needed for calculating highly accurate quantities with the density matrix renormalization group. This is due to the use of a small matrix product operator and to exponentially vanishing tails. Furthermore, its more rapid decay closely mimics the screened Coulomb interaction in three dimensions. Choosing parameters to best match earlier calculations, we report results for the one dimensional hydrogen atom, uniform gas, and small atoms and molecules both exactly and in the local density approximation.
Chemically Reacting One-Dimensional Gas-Particle Flows
NASA Technical Reports Server (NTRS)
Tevepaugh, J. A.; Penny, M. M.
1975-01-01
The governing equations for the one-dimensional flow of a gas-particle system are discussed. Gas-particle effects are coupled via the system momentum and energy equations with the gas assumed to be chemically frozen or in chemical equilibrium. A computer code for calculating the one-dimensional flow of a gas-particle system is discussed and a user's input guide presented. The computer code provides for the expansion of the gas-particle system from a specified starting velocity and nozzle inlet geometry. Though general in nature, the final output of the code is a startline for initiating the solution of a supersonic gas-particle system in rocket nozzles. The startline includes gasdynamic data defining gaseous startline points from the nozzle centerline to the nozzle wall and particle properties at points along the gaseous startline.
Tunneling effects in a one-dimensional quantum walk
Mostafa Annabestani; Seyed Javad Akhtarshenas; Mohamad Reza Abolhassani
2010-04-25
In this article we investigate the effects of shifting position decoherence, arisen from the tunneling effect in the experimental realization of the quantum walk, on the one-dimensional discreet time quantum walk. We show that in the regime of this type of noise the quantum behavior of the walker does not fade, in contrary to the coin decoherence for which the walker undergos the quantum-to-classical transition even for weak noise. Particularly, we show that the quadratic dependency of the variance on the time and also the coin-position entanglement, i.e. two important quantum aspects of the coherent quantum walk, are preserved in the presence of tunneling decoherence. Furthermore, we present an explicit expression for the probability distribution of decoherent one-dimensional quantum walk in terms of the corresponding coherent probabilities, and show that this type of decoherence smooths the probability distribution.
Quantum circuit complexity of one-dimensional topological phases
NASA Astrophysics Data System (ADS)
Huang, Yichen; Chen, Xie
2015-05-01
Topological quantum states cannot be created from product states with local quantum circuits of constant depth and are in this sense more entangled than topologically trivial states, but how entangled are they? Here we quantify the entanglement in one-dimensional topological states by showing that local quantum circuits of linear depth are necessary to generate them from product states. We establish this linear lower bound for both bosonic and fermionic one-dimensional topological phases and use symmetric circuits for phases with symmetry. We also show that the linear lower bound can be saturated by explicitly constructing circuits generating these topological states. The same results hold for local quantum circuits connecting topological states in different phases.
Spatiotemporal fermionization of strongly interacting one-dimensional bosons
NASA Astrophysics Data System (ADS)
Guarrera, Vera; Muth, Dominik; Labouvie, Ralf; Vogler, Andreas; Barontini, Giovanni; Fleischhauer, Michael; Ott, Herwig
2012-08-01
Building on the recent experimental achievements obtained with scanning electron microscopy on ultracold atoms, we study one-dimensional Bose gases in the crossover between the weakly (quasicondensate) and the strongly interacting (Tonks-Girardeau) regime. We measure the temporal two-particle correlation function and compare it with calculations performed using the time-evolving block decimation algorithm. More pronounced antibunching is observed when entering the more strongly interacting regime. Even though this mimics the onset of a fermionic behavior, we highlight that the exact and simple duality between one-dimensional bosons and fermions does not hold when such a dynamical response is probed. The onset of fermionization is also reflected in the density distribution, which we measure in situ to extract the relevant parameters and to identify the different regimes. Our results show agreement between experiment and theory and give insight into the dynamics of strongly correlated many-body systems.
Adiabatic Nonlinear Probes of One-Dimensional Bose Gases
NASA Astrophysics Data System (ADS)
de Grandi, C.; Barankov, R. A.; Polkovnikov, A.
2008-12-01
We discuss two complimentary problems: adiabatic loading of one-dimensional bosons into an optical lattice and merging two one-dimensional Bose systems. Both problems can be mapped to the sine-Gordon model. This mapping allows us to find power-law scalings for the number of excitations with the ramping rate in the regime where the conventional linear response approach fails. We show that the exponent of this power law is sensitive to the interaction strength. In particular, the response is larger, or less adiabatic, for strongly (weakly) interacting bosons for the loading (merging) problem. Our results illustrate that in general the nonlinear response to slow relevant perturbations can be a powerful tool for characterizing properties of interacting systems.
Theoretical studies in quasi-one-dimensional conductors
Hsi-Sheng Goan
1999-01-01
This dissertation first focuses on recent developments in the theory of the quantum Hall effect (QHE) in the magnetic-field-induced spin-density-wave (FISDW) state of the quasi-one-dimensional (Q1D) organic conductors (TMTSF) 2X. The origin and the basic features of the FISDW are reviewed. The QHE in the pinned FISDW state is derived in several simple, transparent ways, including the edge states formulation
Trapped one-dimensional Bose gas as a Luttinger liquid
NASA Astrophysics Data System (ADS)
Monien, H.; Linn, M.; Elstner, N.
1998-11-01
The low-energy fluctuations of a trapped, interacting quasi-one-dimensional Bose gas are studied. Our considerations apply to experiments with highly anisotropic traps. We show that under suitable experimental conditions the system can be described as a Luttinger liquid. This implies that the correlation function of the bosons decays algebraically, preventing Bose-Einstein condensation. At significantly lower temperatures a finite-size gap destroys the Luttinger liquid picture and Bose-Einstein condensation is again possible.
Transport in a one-dimensional Luttinger liquid
Matthew P. A. Fisher; Leonid I. Glazman
1996-01-01
In this paper we review recent theoretical results for transport in a one-dimensional (1d) Luttinger liquid. For simplicity, we ignore electron spin, and focus exclusively on the case of a single-mode. Moreover, we consider only the effects of a single (or perhaps several) spatially localized impurities. Even with these restrictions, the predicted behavior is very rich, and strikingly different than
Bifurcations of One-Dimensional Stochastic Differential Equations
Hans Crauel; Peter Imkeller; Marcus Steinkamp
We consider families of random dynamical systems induced by parametrized one-dimensional stochastic differential equations.\\u000a We give necessary and sufficient conditions on the invariant measures of the associated Markov semigroups which ensure a stochastic\\u000a bifurcation. This leads to sufficient conditions on drift and diffusion coefficients for a stochastic pitchfork and transcritical\\u000a bifurcation of the family of random dynamical systems.
Quantum phases of a one-dimensional dipolar Fermi gas
NASA Astrophysics Data System (ADS)
Mosadeq, Hamid; Asgari, Reza
2015-02-01
We quantitatively obtain the quantum ground-state phases of a Fermi system with on-site and dipole-dipole interactions in one-dimensional lattice chains within the density matrix renormalization group. We show, at a given spin polarization, the existence of six phases in the phase diagram and find that the phases are highly dependent on the spin degree of freedom. These phases can be constructed using available experimental techniques.
Effects of lasing in a one-dimensional quantum metamaterial
NASA Astrophysics Data System (ADS)
Asai, Hidehiro; Savel'ev, Sergey; Kawabata, Shiro; Zagoskin, Alexandre M.
2015-04-01
Electromagnetic pulse propagation in a quantum metamaterial, an artificial, globally quantum coherent optical medium, is numerically simulated. We show that a one-dimensional quantum metamaterial based on superconducting quantum bits, initialized in an easily reachable factorized excited state, demonstrates lasing in the microwave range, accompanied by the chaotization of qubit states and generation of higher harmonics. These effects may provide a tool for characterization and optimization of quantum metamaterial prototypes.
Growth of one-dimensional single-crystalline hydroxyapatite nanorods
NASA Astrophysics Data System (ADS)
Ren, Fuzeng; Ding, Yonghui; Ge, Xiang; Lu, Xiong; Wang, Kefeng; Leng, Yang
2012-06-01
A facile, effective and template/surfactant-free hydrothermal route in the presence of sodium bicarbonate was developed to synthesize highly uniform single-crystalline hydroxyapatite (HA) nanorods with the lengths of several hundred nanometers and aspect ratio up to ˜20. One dimensional (1-D) growth and aspect ratio could be controlled by hydrothermal reaction time and temperature. The longitudinal axis, also the growth direction of the nanorods, is parallel to the [001] direction of HA hexagonal crystal structure.
Cooling of a one-dimensional Bose gas
Bernhard Rauer; Pjotrs Grišins; Igor E. Mazets; Thomas Schweigler; Wolfgang Rohringer; Remi Geiger; Tim Langen; Jörg Schmiedmayer
2015-05-18
We study the dynamics of a degenerate one-dimensional Bose gas that is subject to outcoupling of atoms. Although standard evaporative cooling is rendered ineffective by the absence of thermalizing collisions in this system, we observe substantial cooling. This cooling proceeds through homogeneous particle dissipation and many-body dephasing, enabling the preparation of otherwise unexpectedly low temperatures. Our observations establish a scaling relation between temperature and particle number, and provide insights into equilibration in the quantum world.
Acoustic wave propagation in a one-dimensional layered system.
Luan, P G; Ye, Z
2001-06-01
Propagation of acoustic waves in a one-dimensional water duct containing many air filled blocks is studied by the transfer matrix formalism. Energy distribution and interface vibration of the air blocks are computed. For periodic arrangement, band structure is calculated analytically, whereas the Lyapunov exponent and its variance are computed numerically for random situations. A distinct collective behavior for localized waves is found. The results are also compared with optical situations. PMID:11415246
One-dimensional photonic band gaps in optical lattices
Samoylova, Marina; Holynski, Michael; Courteille, Philippe Wilhelm; Bachelard, Romain
2013-01-01
The phenomenon of photonic band gaps in one-dimensional optical lattices is reviewed using a microscopic approach. Formally equivalent to the transfer matrix approach in the thermodynamic limit, a microscopic model is required to study finite-size effects, such as deviations from the Bragg condition. Microscopic models describing both scalar and vectorial light are proposed, as well as for two- and three-level atoms. Several analytical results are compared to experimental data, showing a good agreement.
Acoustic wave propagation in a one-dimensional layered system
Luan, Pi-Gang; Ye, Zhen
2001-06-01
Propagation of acoustic waves in a one-dimensional water duct containing many air filled blocks is studied by the transfer matrix formalism. Energy distribution and interface vibration of the air blocks are computed. For periodic arrangement, band structure is calculated analytically, whereas the Lyapunov exponent and its variance are computed numerically for random situations. A distinct collective behavior for localized waves is found. The results are also compared with optical situations.
Anyons in one-dimensional lattices: a photonic realization.
Longhi, Stefano; Della Valle, Giuseppe
2012-06-01
Anyons are nonlocal quasi-particles carrying fractional statistics that interpolate between bosons and fermions. Here we propose a photonic realization of anyons moving on a one-dimensional lattice, which is based on light transport in an engineered square array of optical waveguides with a helically bent axis. Our photonic simulator enables visualization of the nonlocal nature of anyons in Fock space and the persistence of correlated tunneling even in the absence of particle interaction. PMID:22660154
Thermalization in a one-dimensional integrable system
Grisins, Pjotrs [Vienna Center for Quantum Science and Technology, Atominstitut, TU Wien, A-1020 Vienna (Austria); Mazets, Igor E. [Vienna Center for Quantum Science and Technology, Atominstitut, TU Wien, A-1020 Vienna (Austria); Ioffe Physico-Technical Institute, 194021 St. Petersburg (Russian Federation)
2011-11-15
We present numerical results demonstrating the possibility of thermalization of single-particle observables in a one-dimensional system, which is integrable in both the quantum and classical (mean-field) descriptions (a quasicondensate of ultracold, weakly interacting bosonic atoms are studied as a definite example). We find that certain initial conditions admit the relaxation of single-particle observables to the equilibrium state reasonably close to that corresponding to the Bose-Einstein thermal distribution of Bogoliubov quasiparticles.
Alpha-Continuity Properties of One-Dimensional Quasicrystals
David Damanik
1997-01-01
We apply the Jitomirskaya-Last extension of the Gilbert-Pearson theory to discrete one-dimensionalSchrodinger operators with potentials arising from generalized Fibonacci sequences. We prove for certainrotation numbers that for every value of the coup ling constant, there exists an ff ? 0 such that thecorresponding operator has purely ff-continuous spectrum. This result follows from uniform upper andlower bounds for the k \\\\Delta
On numerical modeling of one-dimensional geothermal histories
Haugerud, R.A.
1989-01-01
Numerical models of one-dimensional geothermal histories are one way of understanding the relations between tectonics and transient thermal structure in the crust. Such models can be powerful tools for interpreting geochronologic and thermobarometric data. A flexible program to calculate these models on a microcomputer is available and examples of its use are presented. Potential problems with this approach include the simplifying assumptions that are made, limitations of the numerical techniques, and the neglect of convective heat transfer. ?? 1989.
Anomalous velocity fluctuation in one-dimensional defect turbulence
NASA Astrophysics Data System (ADS)
Uchiyama, Yusuke; Kadoya, Takanori; Konno, Hidetoshi
2015-02-01
In this paper various eccentric hole dynamics are presented in defect turbulence of the one-dimensional complex Ginzburg-Landau equation. Each hole shows coherent particlelike motion with nonconstant velocity. On the other hand, successive hole velocities without discriminating each hole exhibit anomalous intermittent motions being subject to multi-time-scale non-Gaussian statistics. An alternate non-Markov stochastic differential equation is proposed, by which all these observed statistical properties can be described successfully.
Mean cover time of one-dimensional persistent random walks.
Chupeau, Marie; Bénichou, Olivier; Voituriez, Raphaël
2014-06-01
The cover time is defined as the time needed for a random walker to visit every site of a confined domain. Here, we focus on persistent random walks, which provide a minimal model of random walks with short-range memory. We derive the exact expression of the mean cover time of a one-dimensional lattice by such a persistent random walk, both for periodic and reflecting boundary conditions. PMID:25019746
Harmonic oscillator in a one-dimensional box
Paolo Amore; Francisco M. Fernandez
2009-07-31
We study a harmonic molecule confined to a one--dimensional box with impenetrable walls. We explicitly consider the symmetry of the problem for the cases of different and equal masses. We propose suitable variational functions and compare the approximate energies given by the variation method and perturbation theory with accurate numerical ones for a wide range of values of the box length. We analyze the limits of small and large box size.
Effective Bragg conditions in a one-dimensional quasicrystal.
Hsueh, W J; Chang, C H; Cheng, Y H; Wun, S J
2012-11-19
We present occurrence of the effective Bragg conditions with wide gapwidth and high reflectance in a Fibonacci superlattice, which is a typical one-dimensional quasicrystal. In the Fibonacci material, the number of effective Bragg conditions is two rather than one which appears in traditional periodic structures. Based on the effective Bragg conditions, this study proposes existence of omnidirectional, wideband and high reflectance in the quasiperiodic materials analogous to that in traditional materials. PMID:23187516
Nonlocally related PDE systems for one-dimensional nonlinear elastodynamics
G. Bluman; A. F. Cheviakov; J.-F. Ganghofierc
2008-01-01
Complete dynamical PDE systems of one-dimensional nonlinear elasticity satisfying the principle of material frame indifference\\u000a are derived in Eulerian and Lagrangian formulations. These systems are considered within the framework of equivalent nonlocally\\u000a related PDE systems. Consequently, a direct relation between the Euler and Lagrange systems is obtained. Moreover, other equivalent\\u000a PDE systems nonlocally related to both of these familiar systems
Cooling of a one-dimensional Bose gas
Bernhard Rauer; Pjotrs Grišins; Igor E. Mazets; Thomas Schweigler; Wolfgang Rohringer; Remi Geiger; Tim Langen; Jörg Schmiedmayer
2015-06-17
We experimentally study the dynamics of a degenerate one-dimensional Bose gas that is subject to a continuous outcoupling of atoms. Although standard evaporative cooling is rendered ineffective by the absence of thermalizing collisions in this system, we observe substantial cooling. This cooling proceeds through homogeneous particle dissipation and many-body dephasing, enabling the preparation of otherwise unexpectedly low temperatures. Our observations establish a scaling relation between temperature and particle number, and provide insights into equilibration in the quantum world.
Pattern formation in the one-dimensional Gray - Scott model
Arjen Doelman; Tasso J. Kaper; Paul A. Zegeling
1997-01-01
In this work, we analyse a pair of one-dimensional coupled reaction-diffusion equations known as the Gray - Scott model, in which self-replicating patterns have been observed. We focus on stationary and travelling patterns, and begin by deriving the asymptotic scaling of the parameters and variables necessary for the analysis of these patterns. Single-pulse and multi-pulse stationary waves are shown to
Spontaneous emission in one-dimensional photonic crystal lasers
Anna Tyszka-Zawadzka; Marcin Koba; Pawel Szczepanski
In this paper, we present an analysis of the spontaneous emission noise in one-dimensional photonic crystal (1D PC) laser. We use semi analytical approach based on stationary solution of the Fokker-Planck equation. Drift and diffusion coefficients, which are necessary to formulate the Fokker-Planck equation, are received from the set of Langevin equations. We derive the exact analytic expressions relating mean
Gravitational anomalies and one dimensional behaviour of black holes
Majhi, Bibhas Ranjan
2015-01-01
It has been pointed out by Bekenstein and Mayo that the behavior of the Black hole's entropy or information flow is similar to that through one-dimensional channel. Here I analyse the same issue with the use of gravitational anomalies. The rate of the entropy change ($\\dot{S}$) and the power ($P$) of the Hawking emission are calculated from the relevant components of the anomalous stress-tensor under the Unruh vacuum condition. I show that the dependence of $\\dot{S}$ on power is $\\dot{S}\\propto P^{1/2}$ which is identical to that for the information flow in one dimensional system. This is established by using the ($1+1$) dimensional gravitational anomalies first. Then the fact is further bolstered by considering the ($1+3$) dimensional gravitational anomalies. It is found that in the former case, the proportionality constant is exactly identical to one dimensional situation, known as Pendry's formula, while in later situation its value decreases.
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.
NASA Astrophysics Data System (ADS)
Wu, Jing-Yun; Yang, Ciao-Wei; Chen, Hui-Fang; Jao, Yu-Chen; Huang, Sheng-Ming; Tsai, Chiitang; Tseng, Tien-Wen; Lee, Gene-Hsiang; Peng, Shie-Ming; Lu, Kuang-Lieh
2011-07-01
Two Cd(HBimc)-based isomers, [Cd(HBimc N)(HBimc T)(H 2O)]·3.5H 2O·EtOH ( 1a·3.5H 2O·EtOH, H 2Bimc=1 H-benzimidazole-5-carboxylic acid) and [Cd(HBimc N)(HBimc T)(H 2O)] ( 1b), and two Cu(HMBimc)-based coordination polymers, [Cu(HMBimc N) 2(H 2O)]·1/2H 2O ( 2·1/2H 2O, H 2MBimc=2-methyl-1 H-benzimidazole-5-carboxylic acid) and [Cu(HMBimc T) 2]·2THF·H 2O ( 3·2THF·H 2O), were self-assembled from Cd(ClO 4) 2·6H 2O/H 2Bimc and Cu(ClO 4) 2·6H 2O/H 2MBimc systems, respectively. Compound 1a adopts a ladder-like chain structure, comprised of a hydrogen-bond-stabilized Cd 2(HBimc N) 2-metallocyclic stair and a 1D straight -(Cd-HBimc T) n- edge, whereas compound 1b exhibits a 2D (4,4)-rhombus layered structure, intercrossed by 1D -(Cd-HBimc N) n- chains and -(Cd-HBimc T) n- chains. Compound 2 shows a 1D double-stranded wave-like chain from two single-stranded wave-like -(Cu-HMBimc N) n- chains and compound 3 adopts a 2D (4,4)-topological layer structure, intercrossed by subunits of 1D -(Cu-HMBimc T) n- chains. Interestingly, a pair of tautomeric HBimc building blocks—normal ( N or HBimc N) and tautomer ( T or HBimc T)—is simultaneously included in the structures of 1a and 1b, whilst the N- and T-configured HMBimc building blocks are present as separate entities in Cu species, 2 and 3, respectively. The existence of only a tautomer ( T) mode of the benzimidazolecarboxylate-based ligand in a Cu(II) network is observed for the first time.
Karabach, Yauhen Y; Kirillov, Alexander M; Haukka, Matti; Kopylovich, Maximilian N; Pombeiro, Armando J L
2008-01-01
The new inorganic 1D coordination polymer [Cu2(H3tea)2(mu4-pma)]n has been prepared, via self-assembly in aqueous medium, from copper(II) nitrate, triethanolamine (H3tea), pyromellitic acid (H4pma) and lithium hydroxide, and characterized by IR spectroscopy, elemental and single-crystal X-ray diffraction analyses. This compound and the related 2D polymer [Cu2(mu-H2tea)(2){mu3-Na2(H2O)4}(mu6-pma)]n.10nH2O are shown to mimic the alkane partial oxidation activity of the multicopper particulate methane monooxygenase, acting as catalysts precursors for the peroxidative oxidation of cyclohexane into cyclohexanol and cyclohexanone, by hydrogen peroxide (as green oxidant) and at room temperature in acidic MeCN/H2O medium. An overall yield (based on cyclohexane) of 29% has been achieved. PMID:18177944
Fang, Wei-Hui; Yang, Guo-Yu, E-mail: ygy@fjirsm.ac.cn
2014-04-01
Three lanthanide–transition-metal coordination polymers, namely, [Er{sub 2}L{sub 6}(H{sub 2}O)][Cu{sub 2}I{sub 2}] (1), [ErL{sub 3}][CuI] (2), and [Dy{sub 2}L{sub 6}(BPDC){sub 0.5}(H{sub 2}O){sub 4}][Cu{sub 3}I{sub 2}] (3) (HL=4-pyridin-3-yl-benzoic acid, H{sub 2}BPDC=4,4?-biphenyldicarboxylic acid) have been made by reacting Ln{sub 2}O{sub 3} and CuI with HL at different temperatures under hydrothermal conditions. All the complexes are characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction, respectively. 1–3 all construct from dimeric (Ln{sub 2}) and (Cu{sub 2}) units and exhibit two types of the structural features: 1 is a two-dimensional layer, 2–3 are three-dimensional frameworks. Interestingly, the in situ formation of the BPDC ligand is found in the structure of 3. The distinct architectures of these complexes indicated that the reaction temperature plays an important role in the formation of higher dimensional coordination polymers. - Graphical abstract: By hydrothermal reaction of lanthanide oxide, copper halide, and 4-pyridin-3-yl-benzoic ligand at different temperatures, a series of 1-D to 3-D 3d–4f coordination polymers, namely [ErL{sub 3}(H{sub 2}O){sub 2}][CuI], [Er{sub 2}L{sub 6}(H{sub 2}O)][Cu{sub 2}I{sub 2}], [ErL{sub 3}][CuI], and [Dy{sub 2}L{sub 6}(BPDC){sub 0.5}(H{sub 2}O){sub 4}][Cu{sub 3}I{sub 2}], have been made, respectively. - Highlights: • Three novel heterometallic coordination polymers derived from 4-pyridin-3-yl-benzoic acid have been hydrothermally synthesized. • Mixed dinuclear motifs of (Ln{sub 2}) and (Cu{sub 2}) serve as secondary building units to generate 2-D layer and 3-D frameworks. • It is proved that higher temperature is apt to permit construction of high dimensional architectures.
Jamie L. Manson; Atta M. Arif; Christopher D. Incarvito; Louise M. Liable-Sands; Arnold L. Rheingold; Joel S. Miller
1999-01-01
Three novel 1-D coordination polymers consisting of {Mn[N(CN)2]2}? structural units and L=2 pyridines (i.e., 2), 2,2?-bipyridine (i.e., 3), and 4,4?-bipyridine (i.e., 4) have been synthesized and characterized by single crystal X-ray crystallography and magnetic susceptibility studies. Compound 2 crystallizes in the monoclinic space group P21\\/n with a=7.5401 (7) Å, b=13.2643 (4) Å, c=8.6973 (9) Å, ?=114.954 (2)°, V= 788.65 (11)
Jamie L. Manson; Atta M. Arif; Christopher D. Incarvito; Louise M. Liable-Sands; Arnold L. Rheingold; Joel S. Miller
1999-01-01
Three novel 1-D coordination polymers consisting of {Mn[N(CN)2]2}? structural units and L=2 pyridines (i.e., 2), 2,2'-bipyridine (i.e., 3), and 4,4'-bipyridine (i.e., 4) have been synthesized and characterized by single crystal X-ray crystallography and magnetic susceptibility studies. Compound 2 crystallizes in the monoclinic space group P21\\/n with a=7.5401 (7) Å, b=13.2643 (4) Å, c=8.6973 (9) Å, beta=114.954 (2)°, V= 788.65 (11)
NASA Astrophysics Data System (ADS)
Babu, Chatla Naga; Suresh, Paladugu; Das, Prasenjit; Sathyanarayana, Arruri; Ramadurai, Ranjith; Sampath, Natarajan; Prabusankar, Ganesan
2014-03-01
The novel copper (II) coordination polymer decorated with copper (II) monomer of general formula, [{Cu(ONO2)2(4,4?-bpy)(py)2}·{Cu(ONO2)2(Py)4}]n (CuCP) has been obtained from one pot reaction between 4,4?-bipyridine (4,4?-bpy), pyridine (py) and Cu(NO3)2·3H2O. The structural and spectural properties have been analyzed by FT-IR, UV-vis, 1H NMR, single crystal X-ray techniques. Besides, the magnetic susceptibility and thermal properties have also been studied.
NASA Astrophysics Data System (ADS)
Shit, Shyamapada; Chakraborty, Joy; Sen, Soma; Pilet, Guillaume; Desplanches, Cédric; Mitra, Samiran
2008-11-01
A novel 1D coordination chain polymer {[Cu 2(pydc) 2(1,10-phen)(H 2O) 2]·3H 2O} n (pydc = pyridine-2,3-dicarboxylate, 1,10-phen = 1,10-phenantroline) has been synthesised and characterised by elemental analysis, FT-IR spectrum, thermal analysis and variable temperature magnetic susceptibility studies. Single crystal X-ray diffraction measurement of the complex shows two Cu(II) centres are in distorted square pyramidal geometry. The complex shows very interesting hydrogen bonding modes involving the lattice and coordinated water molecules with dicarboxylates. Low temperature magnetic susceptibility studies reveal a weak antiferromagnetic coupling interaction of J = - 5.71 cm -1.
NASA Astrophysics Data System (ADS)
Hao, Jin-Ming; Li, Guang-Yue; Li, Yue-Hua; Cui, Guang Hua
2014-10-01
A novel 1D zinc(II) coordination polymer [Zn(bbbm)Cl2]n (where bbbm = 1,4-bis(N-benzimidazolyl)butane) was synthetized by ZnCl2 and bbbm ligand under hydrothermal conditions, and its structural and spectral properties were studied by both experimental and theoretical techniques. The center zinc(II) ion displays four-coordinated in a tetrahedral geometry by two chloride anions and two N atoms of distinct bbbm ligands. Adjacent chains are further connected into a 2D layer structure through ?-? stacking interactions. Vibrational frequencies of [Zn(bbbm)Cl2]n have been calculated using DFT/B3LYP/TZVP method, and well reproduced IR data. Furthermore, the vertical excitation energies from time-dependent DFT calculation confirmed that the fluorescent peaks at 385 nm and 450 nm could respectively be assigned to the ? ? ?* transition within the bbbm ligands and ? ? n transition from chloride anion to bbbm ligand.
One-Dimensional Scanning Approach to Shock Sensing
NASA Technical Reports Server (NTRS)
Tokars, Roger; Adamovsky, Girgory; Floyd, Bertram
2009-01-01
Measurement tools for high speed air flow are sought both in industry and academia. Particular interest is shown in air flows that exhibit aerodynamic shocks. Shocks are accompanied by sudden changes in density, pressure, and temperature. Optical detection and characterization of such shocks can be difficult because the medium is normally transparent air. A variety of techniques to analyze these flows are available, but they often require large windows and optical components as in the case of Schlieren measurements and/or large operating powers which precludes their use for in-flight monitoring and applications. The one-dimensional scanning approach in this work is a compact low power technique that can be used to non-intrusively detect shocks. The shock is detected by analyzing the optical pattern generated by a small diameter laser beam as it passes through the shock. The optical properties of a shock result in diffraction and spreading of the beam as well as interference fringes. To investigate the feasibility of this technique a shock is simulated by a 426 m diameter optical fiber. Analysis of results revealed a direct correlation between the optical fiber or shock location and the beam s diffraction pattern. A plot of the width of the diffraction pattern vs. optical fiber location reveals that the width of the diffraction pattern was maximized when the laser beam is directed at the center of the optical fiber. This work indicates that the one-dimensional scanning approach may be able to determine the location of an actual shock. Near and far field effects associated with a small diameter laser beam striking an optical fiber used as a simulated shock are investigated allowing a proper one-dimensional scanning beam technique.
Quasi-one-dimensional pair density wave superconducting state
NASA Astrophysics Data System (ADS)
Soto-Garrido, Rodrigo; Cho, Gil Young; Fradkin, Eduardo
2015-05-01
We provide a quasi-one-dimensional model which can support a pair-density-wave (PDW) state, in which the superconducting (SC) order parameter modulates periodically in space, with gapless Bogoliubov quasiparticle excitations. The model consists of an array of strongly interacting one-dimensional systems, where the one-dimensional systems are coupled to each other by local interactions and tunneling of the electrons and Cooper pairs between them. Within the interchain mean-field theory, we find several SC states from the model, including a conventional uniform SC state, PDW SC state, and a coexisting phase of the uniform SC and PDW states. In this quasi-1D regime we can treat the strong correlation physics essentially exactly using bosonization methods and the crossover to the 2D system by means of interchain mean-field theory. The resulting critical temperatures of the SC phases generically exhibit a power-law scaling with the coupling constants of the array, instead of the essential singularity found in weak-coupling BCS-type theories. Electronic excitations with an open Fermi surface, which emerge from the electronic Luttinger liquid systems below their crossover temperature to the Fermi liquid, are then coupled to the SC order parameters via the proximity effect. From the Fermi surface thus coupled to the SC order parameters, we calculate the quasiparticle spectrum in detail. We show that the quasiparticle spectrum can be fully gapped or nodal in the uniform SC phase and also in the coexisting phase of the uniform SC and PDW parameters. In the pure PDW state, the excitation spectrum has a reconstructed Fermi surface in the form of Fermi pockets of Bogoliubov quasiparticles.
Quasi-one-dimensional band in the t- J model
NASA Astrophysics Data System (ADS)
Yamase, H.; Kohno, H.; Fukuyama, H.
We study the two-dimensional (2d) t- J model in a mean filed approximation. Assuming uniform charge distribution, we find that the 2d t- J model has an instability toward forming a quasi-one-dimensional (q-1d) Fermi surface. This q-1d state competes with a d-wave pairing state, which overcomes the q-1d state for a realistic parameter region. However, we can show that the q-1d state coexists with the d-wave pairing state when we introduce a small (about 3%) spatial anisotropy in t and J in the original t- J model.
Temperature in One-Dimensional Bosonic Mott insulators
A. Reischl; K. P. Schmidt; G. S. Uhrig
2005-09-07
The Mott insulating phase of a one-dimensional bosonic gas trapped in optical lattices is described by a Bose-Hubbard model. A continuous unitary transformation is used to map this model onto an effective model conserving the number of elementary excitations. We obtain quantitative results for the kinetics and for the spectral weights of the low-energy excitations for a broad range of parameters in the insulating phase. By these results, recent Bragg spectroscopy experiments are explained. Evidence for a significant temperature of the order of the microscopic energy scales is found.
Resonances for large one-dimensional "ergodic" systems
Frédéric Klopp
2015-06-05
The present paper is devoted to the study of resonances for one-dimensional quantum systems with a potential that is the restriction to some large box of an ergodic potential. For discrete models both on a half-line and on the whole line, we study the distributions of the resonances in the limit when the size of the box where the potential does not vanish goes to infinity. For periodic and random potentials, we analyze how the spectral theory of the limit operator influences the distribution of the resonances.
Cooperative diffusion in one-dimensional lattice gases
NASA Astrophysics Data System (ADS)
Poland, Douglas; Song, Sandra
1993-06-01
We obtain exact time-power series through 11th order for cooperative diffusion in a one-dimensional lattice gas with nearest-neighbor interactions. In the high-temperature limit (single-site exclusion one) mean field theory is exact and the model is soluble for arbitrary initial conditions. The exact solution is used to recast the time-power series for a general temperature as a series in the appropriate function obtained from the high-temperature limit. We discuss why more conventional methods of extracting power-law exponents for the asymptotic long-time behavior do not work well for this model.
Phase-separation transition in one-dimensional driven models.
Kafri, Y; Levine, E; Mukamel, D; Schütz, G M; Willmann, R D
2003-09-01
A class of models of two-species driven diffusive systems which is shown to exhibit phase separation in d=1 dimensions is introduced. Unlike previously studied models exhibiting similar phenomena, here the relative density of the two species is fluctuating within the macroscopic domain of the phase separtated state. The nature of the phase transition from the homogeneous to the phase-separated state is discussed in view of a recently introduced criterion for phase separation in one-dimensional driven systems. PMID:14524817
Criterion for phase separation in one-dimensional driven systems.
Kafri, Y; Levine, E; Mukamel, D; Schütz, G M; Török, J
2002-07-15
A general criterion for the existence of phase separation in driven density-conserving one-dimensional systems is proposed. It is suggested that phase separation is related to the size dependence of the steady-state currents of domains in the system. A quantitative criterion for the existence of phase separation is conjectured using a correspondence made between driven diffusive models and zero-range processes. The criterion is verified in all cases where analytical results are available, and predictions for other models are provided. PMID:12144403
Inverse uniqueness results for one-dimensional weighted Dirac operators
Jonathan Eckhardt; Aleksey Kostenko; Gerald Teschl
2014-07-29
Given a one-dimensional weighted Dirac operator we can define a spectral measure by virtue of singular Weyl-Titchmarsh-Kodaira theory. Using the theory of de Branges spaces we show that the spectral measure uniquely determines the Dirac operator up to a gauge transformation. Our result applies in particular to radial Dirac operators and extends the classical results for Dirac operators with one regular endpoint. Moreover, our result also improves the currently known results for canonical (Hamiltonian) systems. If one endpoint is limit circle case, we also establish corresponding two-spectra results.
Quantum quenches and thermalization in one-dimensional systems
NASA Astrophysics Data System (ADS)
Rigol, Marcos
2010-03-01
We use quantum quenches to study the dynamics and thermalization of hardcore bosons and fermions in finite one-dimensional lattices. We perform exact diagonalizations and find that, far away from integrability, few-body observables thermalize. We then study the breakdown of thermalization as one approaches an integrable point. This is found to be a smooth process in which the predictions of standard statistical mechanics continuously worsen as the system moves toward integrability. We establish a direct connection between the presence or absence of thermalization and the validity or failure of the eigenstate thermalization hypothesis, respectively.ReferencesM. Rigol, Phys. Rev. Lett. 103, 100403 (2009); Phys. Rev. A 80, 053607 (2009).
Bloch Oscillations in a One-Dimensional Spinor Gas
Gangardt, D. M. [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham, B15 2TT (United Kingdom); Kamenev, A. [School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455 (United States)
2009-02-20
A force applied to a spin-flipped particle in a one-dimensional spinor gas may lead to Bloch oscillations of the particle's position and velocity. The existence of Bloch oscillations crucially depends on the viscous friction force exerted by the rest of the gas on the spin excitation. We evaluate the friction in terms of the quantum fluid parameters. In particular, we show that the friction is absent for integrable cases, such as an SU(2) symmetric gas of bosons or fermions. For small deviations from the exact integrability the friction is very weak, opening the possibility to observe Bloch oscillations.
Effective-medium theory for one-dimensional gratings
NASA Astrophysics Data System (ADS)
Tang, Shiwei; Zhu, Baocheng; Jia, Min; He, Qiong; Sun, Shulin; Mei, Yongfeng; Zhou, Lei
2015-05-01
Based on a mode-expansion theory under single-mode approximation, we derived the scatterings parameters for a general one-dimensional photonic grating composed of two different materials, and then established an effective-medium theory for such a composite by equating the obtained scattering parameters to those of a homogeneous medium. Our effective-medium theory well describes the grating structures with general material and geometrical parameters, and recovers two previous formulas, which are valid only at certain limiting conditions. The theory is justified by full-wave simulations and microwave experiments.
Three-Body Recombination in One-Dimensional Systems
NASA Astrophysics Data System (ADS)
Mehta, Nirav; Greene, Chris; Esry, Brett
2006-05-01
Few-body processes in one dimension are of critical importance in the understanding of quantum gases in highly confined trap geometries. We consider three- particle systems for a variety of 2-body interactions using the adiabatic hyperspherical formalism. In particular, we numerically demonstrate that the three-body recombination probability vanishes for zero- range interactions, verifying an old result found by McGuire (1964). We further consider the recombination probability for a variety of finite range interactions and study the dependence on the one- dimensional scattering length. Finally, we present some preliminary results for four-body systems.
Programmers manual for a one-dimensional Lagrangian transport model
Schoellhamer, D.H.; Jobson, H.E.
1986-01-01
A one-dimensional Lagrangian transport model for simulating water-quality constituents such as temperature, dissolved oxygen , and suspended sediment in rivers is presented in this Programmers Manual. Lagrangian transport modeling techniques, the model 's subroutines, and the user-written decay-coefficient subroutine are discussed in detail. Appendices list the program codes. The Programmers Manual is intended for the model user who needs to modify code either to adapt the model to a particular need or to use reaction kinetics not provided with the model. (Author 's abstract)
Two dimensionality in quasi-one-dimensional cobalt oxides
J. Sugiyama; H. Nozaki; J. H. Brewer; E. J. Ansaldo; G. D. Morris; T. Takami; H. Ikuta; U. Mizutani
2006-01-01
Magnetism of quasi-one-dimensional (1D) cobalt oxides An+2Con+1O3n+3 (A=Ca, Sr and Ba, n=1–5 and ?) was investigated by ?+SR using polycrystalline samples, at temperatures from 300K down to 1.8K. The wTF–?+SR experiments showed the existence of a magnetic transition in all six samples investigated. The onset temperature of the transition (Tcon) was found to decrease with n; that is, 100±25, 90±10,
Statistical properties of one-dimensional random lasers.
Zaitsev, Oleg; Deych, Lev; Shuvayev, Vladimir
2009-01-30
Statistical properties of a laser based on a one-dimensional disordered superlattice open at one side are studied numerically. The passive normal modes of the system are determined using the Feshbach projection technique. It is found that the mode competition due to the spacial hole burning leads to a saturation of the number of lasing modes with increasing pump rate. It is also responsible for nonmonotonic dependence of intensities of lasing modes as functions of pumping. Computed distributions of spectral spacing and intensity statistics are in qualitative agreement with experimental results. PMID:19257422
Quantum mechanics of one-dimensional trapped Tonks gases
M. D. Girardeau; E. M. Wright
2001-04-30
Several experimental groups are currently working towards realizing quasi-one-dimensional (1D) atom waveguides and loading them with ultracold atoms. The dynamics becomes truly 1D in a regime (Tonks gas) of low temperatures and densities and large positive scattering lengths for which the transverse mode becomes frozen, in which case the many-body Schrodinger dynamics becomes exactly soluble via a Fermi-Bose mapping theorem. In this paper we review our recent work on the exact ground state and quantum dynamics of 1D Tonks gases and assess the possibility of approaching the Tonks regime using Bessel beam optical dipole traps.
Retrieved Anisotropy of One-Dimensional Crystal Piperidinium Triblomoplumbate
NASA Astrophysics Data System (ADS)
Azuma, Junpei; Tanaka, Koichiro
Polarization characteristics of luminescence in one-dimensional crystal piperidinium tribromoplumbate has been investigated to clarify the relaxed photo-excited states of this system. It has been observed that the emission band with non-exponential decay is almost depolarized at 10 K but becomes polarized drastically parallel to the chain as temerature is raised above 15 K. This indicates that anisotropy of the initial state of luminescence retrieved thermally. Electron spin resonance (ESR) technique has been applied to identify photo-induced defects. A hole center formed by several bromine ions has been observed. The initial state of this emission band is discussed from the retrieved anisotropy and the ESR measurements.
Retrieved Anisotropy of One-Dimensional Crystal Piperidinium Triblomoplumbate
NASA Astrophysics Data System (ADS)
Azuma, Junpei; Tanaka, Koichiro
2001-08-01
Polarization characteristics of luminescence in one-dimensional crystal piperidinium tribromoplumbate has been investigated to clarify the relaxed photo-excited states of this system. It has been observed that the emission band with non-exponential decay is almost depolarized at 10 K but becomes polarized drastically parallel to the chain as temperature is raised above 15 K. This indicates that anisotropy of the initial state of luminescence retrieved thermally. Electron spin resonance (ESR) technique has been applied to identify photo-induced defects. A hole center formed by several bromine ions has been observed. The initial state of this emission band is discussed from the retrieved anisotropy and the ESR measurements.
Phase sticking in one-dimensional Josephson junction chains
NASA Astrophysics Data System (ADS)
Ergül, Adem; Schaeffer, David; Lindblom, Magnus; Haviland, David B.; Lidmar, Jack; Johansson, Jan
2013-09-01
We studied current-voltage characteristics of long one-dimensional Josephson junction chains with Josephson energy much larger than charging energy, EJ?EC. In this regime, typical I-V curves of the samples consist of a supercurrent-like branch at low-bias voltages followed by a voltage-independent chain current branch, Ichain at high bias. Our experiments showed that Ichain is not only voltage-independent but it is also practically temperature-independent up to T=0.7TC. We have successfully model the transport properties in these chains using a capacitively shunted junction model with nonlinear damping.
Spatial stochastic resonance in one-dimensional Ising systems.
Néda, Z; Rusz, A; Ravasz, E; Lakdawala, P; Gade, P M
1999-10-01
The one-dimensional Ising model is analytically studied in a spatially periodic and oscillatory external magnetic field using the transfer-matrix method. For low enough magnetic field intensities the correlation between the external magnetic field and the response in magnetization presents a maximum for a given temperature. The phenomenon can be interpreted as a resonance phenomenon induced by the stochastic heat bath. This "spatial stochastic resonance" is realized in the equilibrium state and not as a dynamical response to the external time-periodic driving. PMID:11970258
One-dimensional modeling of secondary clarifiers for wastewater treatment
Watts, R.W. [Merck & Co., Inc., Whitehouse Station, NJ (United States); Svoronos, S.A.; Koopman, B. [Univ. of Florida, Gainesville, FL (United States)
1996-12-31
A one-dimensional model of activated sludge secondary clarifiers with a variable dispersion coefficient dependent on concentration and feed velocity was developed. Data collected from a full-scale clarifier at the Kanapaha Water Reclamation Facility in Gainesville, FL were used to evaluate this model. Data from three experimental periods demonstrated the ability of the model to predict steady state sludge blanket levels as well as clarifier failure. The variable dispersion coefficient model outperformed other well-known models in predicting clarifier overloading. 15 refs., 1 fig., 3 tabs.
One-dimensional parabolic-beam photonic crystal laser.
Ahn, Byeong-Hyeon; Kang, Ju-Hyung; Kim, Myung-Ki; Song, Jung-Hwan; Min, Bumki; Kim, Ki-Soo; Lee, Yong-Hee
2010-03-15
We report one-dimensional (1-D) parabolic-beam photonic crystal (PhC) lasers in which the width of the PhC slab waveguide is parabolically tapered. A few high-Q resonant modes are confirmed in the vicinity of the tapered region where Gaussian-shaped photonic well is formed. These resonant modes originate from the dielectric PhC guided mode and overlap with the gain medium efficiently. It is also shown that the far-field radiation profile is closely associated with the symmetry of the structural perturbation. PMID:20389580
Numerical computations on one-dimensional inverse scattering problems
NASA Technical Reports Server (NTRS)
Dunn, M. H.; Hariharan, S. I.
1984-01-01
An approximate method to determine the index of refraction of a dielectric obstacle is presented. For simplicity one dimensional models of electromagnetic scattering are treated. The governing equations yield a second order boundary value problem, in which the index of refraction appears as a functional parameter. The availability of reflection coefficients yield two additional boundary conditions. The index of refraction by a k-th order spline which can be written as a linear combination of B-splines is approximated. For N distinct reflection coefficients, the resulting N boundary value problems yield a system of N nonlinear equations in N unknowns which are the coefficients of the B-splines.
Numerical computations on one-dimensional inverse scattering problems
NASA Technical Reports Server (NTRS)
Dunn, M. H.; Hariharan, S. I.
1983-01-01
An approximate method to determine the index of refraction of a dielectric obstacle is presented. For simplicity one dimensional models of electromagnetic scattering are treated. The governing equations yield a second order boundary value problem, in which the index of refraction appears as a functional parameter. The availability of reflection coefficients yield two additional boundary conditions. The index of refraction by a k-th order spline which can be written as a linear combination of B-splines is approximated. For N distinct reflection coefficients, the resulting N boundary value problems yield a system of N nonlinear equations in N unknowns which are the coefficients of the B-splines.
NASA Astrophysics Data System (ADS)
Sun, Yanchun; Wang, Yufang; Li, Zhuo; Zhao, Jianshe; Zhang, Shichao
2014-09-01
A novel coordination polymer {[Mn2(L)4/3(H2O)3]?2H2O}n(1), was synthesized by the hydrothermal reaction of 4,4?-[(5-carboxy-1,3-phenylene)bis(oxy)]dibenzoic acid (H3L) with manganese(II) chloride tetrahydrate (MnCl2?4H2O) in an aqueous solution. The single X-ray diffraction indicated that the coordination polymer 1 had a three-dimensional (3D) framework. A trinuclear Mn unit is utilized as a building block connected via oxygen atoms of carboxylate group to form a two-dimensional layer structure. The interlayers connected by the ligands result in a 3D architecture. The coordination polymer 1 was characterized by the infrared spectroscopy, elemental analysis and powder XRD. According to magnetic susceptibility measurements the coordination polymer 1 can be characterized with the antiferromagnetic coupling interaction of J = -3.21 cm-1. Furthermore, the thermogravimetric analysis revealed good thermal stability for the coordination polymer 1.
Nanostructured metal surfaces as quasi-one-dimensional model systems
NASA Astrophysics Data System (ADS)
Dona, E.; Amann, P.; Cordin, M.; Menzel, A.; Bertel, E.
2008-05-01
The physics of quasi-one-dimensional systems deviates considerably from that of higher dimensional systems and is not yet completely understood. The phase diagram is surprisingly complicated and technologically highly interesting. This presentation focuses on the Pt(1 1 0) surface and halogen/Pt(1 1 0) adsorption systems as models for quasi-one-dimensional behaviour. The dimensional reduction results in a reduced screening and the onset of correlation effects despite the presence of the metallic bulk. Anomalous features in the electronic structure as probed by angle-resolved photoemission are observed and reveal indeed a significant correlation in the system. The phase diagram of the halogen/Pt(1 1 0) adsorption system is studied in detail by scanning tunnelling microscopy (STM) and low-energy electron diffraction (LEED) spot profile analysis. Analysis of the experimental data reveals the presence of fluctuations over a surprisingly large range of the phase diagram. Counter-intuitively, the long-range order of a uniform room temperature phase is destructed as the temperature is lowered. At 50 K three different phases coexist in an anisotropic glassy state. The anomalous loss of long-range order upon cooling is attributed to an electronically driven instability.
Normal and generalized Bose condensation in traps: One dimensional examples
Andras Suto
2004-12-16
We prove the following results. (i) One-dimensional Bose gases which interact via unscaled integrable pair interactions and are confined in an external potential increasing faster than quadratically undergo a complete generalized Bose-Einstein condensation (BEC) at any temperature, in the sense that a macroscopic number of particles are distributed on a o(N)number of one-particle states. (ii) In a one dimensional harmonic trap the replacement of the oscillator frequency \\omega by \\omega\\ln N/N gives rise to a phase transition at a=\\hbar\\omega\\beta=1 in the noninteracting gas. For a/N^a tends to 1. For a>1 there is BEC with a condensate density /N going to 1-1/a. For a>=1, (\\ln N/N)(n_0-) is asymptotically distributed following Gumbel's law. For any a>0 the free energy is -(\\pi^2/6a\\beta)N/\\ln N+o(N/\\ln N), with no singularity at a=1. (iii) In Model (ii) both above and below the critical temperature the the gas undergoes a complete generalized BEC, thus providing a coexistence of ordinary and generalized condensates below the critical point. (iv) Adding an interaction =o(N\\ln N) to Model (ii) we prove that a complete generalized BEC occurs at all temperatures.
Normal and Generalized Bose Condensation in Traps: One Dimensional Examples
NASA Astrophysics Data System (ADS)
Süt?, András
2004-10-01
We prove the following results. (i) One-dimensional Bose gases which interact via unscaled integrable pair interactions and are confined in an external potential increasing faster than quadratically undergo a complete generalized Bose-Einstein condensation (BEC) at any temperature, in the sense that a macroscopic number of particles are distributed on a o( N) number of one-particle states. (ii) In a one dimensional harmonic trap the replacement of the oscillator frequency ? by ? N/ N gives rise to a phase transition at a??? = 1 in the noninteracting gas. For a < 1 the limit distribution of n 0/ N a is exponential and < n 0>/ N a ? 1. For a > 1 there is BEC with a condensate density < n 0>/ N ? 1 - a -1. For a 1, ( N/ N)( n 0-< n 0>) is asymptotically distributed following Gumbel's law. For any a > 0 the free energy is -(?2/6? a) N/ N+ o( N/ N), with no singularity at a = 1. (iii) In Model (ii) both above and below the critical temperature the gas undergoes a complete generalized BEC, thus providing a coexistence of ordinary and generalized condensates below the critical point. (iv) Adding an interaction < U N > = o( N N) to Model (ii) we prove that a complete generalized BEC occurs for any ?>0.
Dislocation-mediated melting of one-dimensional Rydberg crystals
Sela, Eran; Garst, Markus [Institut fuer Theoretische Physik, Universitaet zu Koeln, Zuelpicher Str. 77, DE-50937 Koeln (Germany); Punk, Matthias [Physik Department, Technische Universitaet Muenchen, James-Franck-Strasse, DE-85748 Garching (Germany); Department of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States)
2011-08-15
We consider cold Rydberg atoms in a one-dimensional optical lattice in the Mott regime with a single atom per site at zero temperature. An external laser drive with Rabi frequency {Omega} and laser detuning {Delta} creates Rydberg excitations whose dynamics is governed by an effective spin-chain model with (quasi) long-range interactions. This system possesses intrinsically a large degree of frustration resulting in a ground-state phase diagram in the ({Delta},{Omega}) plane with a rich topology. As a function of {Delta}, the Rydberg blockade effect gives rise to a series of crystalline phases commensurate with the optical lattice that form a so-called devil's staircase. The Rabi frequency {Omega}, on the other hand, creates quantum fluctuations that eventually lead to a quantum melting of the crystalline states. Upon increasing {Omega}, we find that generically a commensurate-incommensurate transition to a floating Rydberg crystal that supports gapless phonon excitations occurs first. For even larger {Omega}, dislocations within the floating Rydberg crystal start to proliferate and a second, Kosterlitz-Thouless-Nelson-Halperin-Young dislocation-mediated melting transition finally destroys the crystalline arrangement of Rydberg excitations. This latter melting transition is generic for one-dimensional Rydberg crystals and persists even in the absence of an optical lattice. The floating phase and the concomitant transitions can, in principle, be detected by Bragg scattering of light.
Adiabatic Hyperspherical Study of One-dimensional Hydrogen Molecule
NASA Astrophysics Data System (ADS)
Yu, Youliang; Wang, Yujun; Esry, Brett
2014-05-01
We present a calculation of the adiabatic hyperspherical potentials for one-dimensional H2. Although the adiabatic hyperspherical representation has proven very useful in understanding atomic systems, especially highly correlated states like doubly excited states, it has not yet been applied to the electronic and nuclear degrees of freedom for a molecule more complicated than H2+.We thus present the first such calculation, albeit for a one-dimensional model of H2. Our model, however, is chosen to exactly reproduce the three-dimensional H2 and H2+ground Born-Oppenheimer potentials. One of our goals is to identify and understand the role of doubly excited states -- which can be readily identified in the adiabatic hyperspherical representation, unlike standard quantum chemistry. We illustrate the method with an application to attosecond physics. We also want to take advantage of the fact that the adiabatic hyperspherical representation produces well defined and discrete effective potentials for all ionization channels to help understand processes like strong-field dissociative ionization. These topics, and others, will be discussed. Supported by the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy.
One dimensional global and local solution for ICRF heating
Wang, C.Y.; Batchelor, D.B.; Jaeger, E.F.; Carter, M.D.
1995-02-01
A numerical code GLOSI [Global and Local One-dimensional Solution for Ion cyclotron range of frequencies (ICRF) heating] is developed to solve one-dimensional wave equations resulting from the use of radio frequency (RF) waves to heat plasmas. The code uses a finite difference method. Due to its numerical stability, the code can be used to find both global and local solutions when imposed with appropriate boundary conditions. Three types of boundary conditions are introduced to describe wave scattering, antenna wave excitation, and fixed tangential wave magnetic field. The scattering boundary conditions are especially useful for local solutions. The antenna wave excitation boundary conditions can be used to excite fast and slow waves in a plasma. The tangential magnetic field boundary conditions are used to calculate impedance matrices, which describe plasma and antenna coupling and can be used by an antenna code to calculate antenna loading. These three types of boundary conditions can also be combined to describe various physical situations in RF plasma heating. The code also includes plasma thermal effects and calculates collisionless power absorption and kinetic energy flux. The plasma current density is approximated by a second-order Larmor radius expansion, which results in a sixth-order ordinary differential equation.
Huang, Xing; Sheng, Peng; Tu, Zeyi; Zhang, Fengjiao; Wang, Junhua; Geng, Hua; Zou, Ye; Di, Chong-an; Yi, Yuanping; Sun, Yimeng; Xu, Wei; Zhu, Daoben
2015-01-01
Currently, studies on organic two-dimensional (2D) materials with special optic-electronic properties are attracting great research interest. However, 2D organic systems possessing promising electrical transport properties are still rare. Here a highly crystalline thin film of a copper coordination polymer, Cu-BHT (BHT=benzenehexathiol), is prepared via a liquid–liquid interface reaction between BHT/dichloromethane and copper(II) nitrate/H2O. The morphology and structure characterization reveal that this film is piled up by nanosheets of 2D lattice of [Cu3(C6S6)]n, which is further verified by quantum simulation. Four-probe measurements show that the room temperature conductivity of this material can reach up to 1,580?S?cm?1, which is the highest value ever reported for coordination polymers. Meanwhile, it displays ambipolar charge transport behaviour and extremely high electron and hole mobilities (99?cm2?V?1?s?1 for holes and 116?cm2?V?1?s?1 for electrons) under field-effect modulation. PMID:26074272
Huang, Xing; Sheng, Peng; Tu, Zeyi; Zhang, Fengjiao; Wang, Junhua; Geng, Hua; Zou, Ye; Di, Chong-An; Yi, Yuanping; Sun, Yimeng; Xu, Wei; Zhu, Daoben
2015-01-01
Currently, studies on organic two-dimensional (2D) materials with special optic-electronic properties are attracting great research interest. However, 2D organic systems possessing promising electrical transport properties are still rare. Here a highly crystalline thin film of a copper coordination polymer, Cu-BHT (BHT=benzenehexathiol), is prepared via a liquid-liquid interface reaction between BHT/dichloromethane and copper(II) nitrate/H2O. The morphology and structure characterization reveal that this film is piled up by nanosheets of 2D lattice of [Cu3(C6S6)]n, which is further verified by quantum simulation. Four-probe measurements show that the room temperature conductivity of this material can reach up to 1,580?S?cm(-1), which is the highest value ever reported for coordination polymers. Meanwhile, it displays ambipolar charge transport behaviour and extremely high electron and hole mobilities (99?cm(2?)V(-1?)s(-1) for holes and 116?cm(2?)V(-1?)s(-1) for electrons) under field-effect modulation. PMID:26074272
NASA Astrophysics Data System (ADS)
Zhou, Bo; Liang, Li-Mei; Yao, Jie
2014-07-01
This work concerns the isomorphous substitution of coordination polymers (CPs) and its effect on the optical and electrochemical properties. The application of CPs in electrochemical sensing was studied as well. Isomorphous coordination polymers, [CoxZn1-xtyr]n (tyr=L-tyrosine), where x (0-1) was controlled by the Co/Zn ratios of raw materials, were successfully synthesized via a hydrothermal method, as proved by XRD and EDS results. Their UV-vis DRS and fluorescence spectra change gradually along with the composition. Cyclic voltammograms of modified electrodes, [CoxZn1-xtyr]n/GCE, show that as more and more Zn replaced Co, the current signal decreases greatly and the potential shifts negatively. Much attention was paid to [Cotyr]n due to its highest sensitivity. Refreshable modified carbon paste electrode, [Cotyr]n-CPE, was used to determine nitrite, and showed pretty good performance as evidenced by chronoamperometry. The response was made very fast within mere 5 s. The linear detection range was from 5.00×10-5 to 3.45×10-3 M, with sensitivity of 263.4 mA mol-1 L cm-2. The detection limit was found to be 2.00×10-5 M. The sensor also showed good antiinterference and reproducibility.
Wang, Han; Wan, Chong-Qing; Mak, Thomas C W
2014-05-21
Two novel coordination polymers [Ag16(SO4)8][Ag4(SO4)2]3(L1)12·nH2O (n = 72) (1) and [Ag10(SO4)5(L2)4(H2O)2]·8H2O (2) based on conformationally variable oligo-?-heteroarylsulfanyl ligands 2-(pyrazin-2-ylthio)-6-(pyridin-2-ylthio)pyrazine (L1) or 2,6-bis(pyrazin-2-ylthio)pyrazine (L2) and sulfate-templated high-nuclearity Ag(I) clusters as structure-building units (SBUs) have been synthesized under mild conditions. Single-crystal X-ray analysis showed that complex 1 exhibits a porous three-dimensional framework containing Ag16(SO4)8 and Ag4(SO4)2 SBUs that are interconnected by L1 ligands, whereas 2 has a much denser network constructed from Ag10(SO4)5 SBUs and L2 linkers. To our knowledge, the Ag16(SO4)8 cluster core found in 1 is the largest sulfate-based polynuclear SBU in coordination polymers, and the 14-connected Ag10(SO4)5 in 2 is the highest-connectivity Ag(I) cluster SBU reported to date. These two complexes were fully characterized by infrared spectroscopy, elemental analysis, powder X-ray diffraction, thermogravimetric analysis and differential scanning calorimetry. PMID:24683599
Dong Wenwen; Zhao Jun [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100039 (China); Xu Li [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China)], E-mail: xli@fjirsm.ac.cn
2008-05-15
Two new coordination polymers, [Ag(tza)]{sub {infinity}} (1) (Htza=tetrazole-1-acetic acid) and [Cu(tza){sub 2}]{sub {infinity}} (2) have been prepared at room temperature and characterized by X-ray crystallography, IR, UV-vis, fluorescence spectra and magnetism analysis. Compound 1 exhibits extended helical chains through bridging ligand tza. The Ag{center_dot}{center_dot}{center_dot}Ag interactions between the adjacent chains form a 3-D framework featuring the extended tza-connected Ag chains that obviously affect the photoluminescent property. Compound 2 features undulated layered structure with hourglass-shaped [Cu{sub 4}(tza){sub 4}] as subunits with the weak ferromagnetic interactions between Cu(II) ions, which are further stabilized by inter-lamellar C-H{center_dot}{center_dot}{center_dot}O hydrogen bonds in the resulting 3-D supramolecular framework. - Graphical abstract: Two novel coordination polymers, [Ag(tza)]{sub {infinity}} (1) and [Cu(tza){sub 2{infinity}} (2) have been prepared and characterized. Compound 1 features extended double-stranded helical chains. Compound 2 features undulated layered structure with hourglass-shaped [Cu{sub 4}(tza){sub 4}] as subunits with the weak ferromagnetic interactions between Cu(II) ions.
NASA Astrophysics Data System (ADS)
Dîrtu, Marinela M.; Schmit, France; Naik, Anil D.; Rotaru, Aurelian; Marchand-Brynaert, Jacqueline; Garcia, Yann
2012-03-01
A new 1D coordination polymer [Fe(?Alatrz)3](ClO4)2 • H2O (1) with a neutral bidentate ligand, ?Alatrz = 4H-1,2,4-triazol-4-yl-propionate, was prepared and its magnetic behavior was investigated by temperature dependent magnetic susceptibility measurements and 57Fe Mössbauer spectroscopy. The temperature dependence of the high-spin molar fraction derived from 57Fe Mössbauer spectroscopy recorded on cooling below room temperature reveals a gradual single step transition with T1/2 = 173 K between high-spin and low-spin states in agreement with magnetic susceptibility measurements. 1 presents striking reversible thermochromism from white, at room temperature, to pink on quench cooling to liquid nitrogen. The phase transition is of first order as deduced from differential scanning calorimetry, with T1/2 matching the one determined by both SQUID and 57Fe Mössbauer spectroscopy. A brief assessment has been made among closely related 1D coordination polymers to perceive the effect of ligand spacer length and anion effect on the spin crossover behavior of these new materials.
Feng, Xun [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Liu, Lang [College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450002 (China); College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Wang, Li-Ya, E-mail: wlya@lynu.edu.cn [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); College of Chemistry and Pharmacy Engineering, Nanyang Normal University, Nanyang 473601 (China); Song, Hong-Liang; Qiang Shi, Zhi; Wu, Xu-Hong [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Ng, Seik-Weng [Department of Chemistry, University of Malaya, Kuala Lumpur 50603 (Malaysia); Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 80203 (Saudi Arabia)
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 case 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.
One-dimensional non-stationary convection model
NASA Astrophysics Data System (ADS)
Sadokov, V. P.; Vasilevsky, K. D.
2012-04-01
One-dimensional convection model is widely used in large-scale atmospheric models for the description of the convective clouds and calculating precipitation. Such models are stationary and can not describe the dynamics of the convection. There are widely used the non-stationary version of the one-dimensional models that are remaining within the framework of the simple versions. Evaluation of the convection processes in these models differs from the stationary version. If we consider the results of the stationary version as an initial condition for the non-stationary model, then in the process of solving the non-stationary task it will be the development of convection and establishing of the convective. In the present paper the equation processes for the vertical velocity are considered. That contains the time derivative. It is solved by the finite-difference scheme for a variety of levels k. The number of the levels k is determined by the spline approximation of the input data. As a result we have a quadratic equation for the vertical velocity w, taking into account the effects of entrainment, detrainment and release of condensation heat. If the vertical velocity in the calculation is positive, we assume the formation of the cloud elements. Based on the equations for the specific humidity q, water content ? and the statistical stability s, and introduce to them the time derivatives we obtain the equations system for the one-dimensional non-stationary cloud model, that take into account the processes occurring inside the cloud and in the surrounding area. Also here is presented an approach for the calculation of the precipitation. Many experiments using the model were performed to optimize the input parameters, empirical coefficients and calculated algorithm. The calculations showed that all model parameters are changing over time and finally the development process is stabilized. This is due to the surrounding state of the atmosphere that does not changed in these calculations. Value of the time steps for the integration in the cloud and the time steps of changing the environment parameters must be conformed: the period of convection is less than the step of change in the external environment. In our case we choose a step in non-stationary cloud model up to 10 seconds. The model is convenient to use because minimum of the input data is required: the geopotential, pressure, temperature and humidity. At the output the model can provide quick calculations and fairly realistic values of the vertical velocity, precipitation, and the various parameters of the clouds. The presented algorithm can be adapted to large-scale hydrodynamical models of the atmosphere.
Soft coordination supramolecular polymers: novel materials for dual electro-Yawei Liang,{a
Huang, Jianbin
to the dynamic nature of coordinating bonds.8,11 In the past decade, various SCSPs of transition and rare earth metals with judicious ligands have been achieved.12,13 It is expected that these metal-containing novel
Bai, Shi-Qiang; Jiang, Lu; Young, David James; Hor, T S Andy
2015-04-01
Quinolyl-1,2,3-triazole ligand supported [Cu4I4] stair-step aggregates [Cu4I4(L1)2] (1), [Cu4I4(L2)2] (2), [Cu4I4(L3)2] (3), [Cu4I4(L4)2] (4), [Cu4I4(L5)2] (5), and six-membered [Cu3I3] metallacycle based coordination polymers [Cu2I2(L6)]n (6) and [Cu2I2(L7)]n (7) (ligands are 2-((1H-1,2,3-triazol-1-yl)methyl)quinoline (L1), 2-((4-alkyl-1H-1,2,3-triazol-1-yl)methyl)quinoline (propyl, butyl and isobutyl for L2, L3 and L4, respectively) and 2-(1-((quinolin-2-yl)methyl)-1H-1,2,3-triazol-4-yl)alcohol (methanol, ethanol and propanol for L5, L6 and L7, respectively)) have been prepared and characterized by single-crystal X-ray diffraction (XRD), powder XRD, photoluminescence spectroscopy and thermogravimetric analysis. Complexes 1-5 are stair-step [Cu4I4] aggregate structures supported by two quinolyl-triazole hybrid ligands. Complexes 6 and 7 are rare cyclic [Cu3I3] aggregate-based 1-D coordination polymers. All ligands adopt a common tridentate-bridging coordination mode. These complexes are strongly luminescent with a yellow emission (500-700 nm) in the solid state. PMID:25727813
NASA Astrophysics Data System (ADS)
Peng, Yi-Ru; Chien, Po-Hsiu; Chung, Huey-Ting; Pan, Pei-Yun; Liu, Yen-Hsiang; Yang, En-Che
2014-04-01
The reaction of 1,2,4-benzenetricarboxylic acid (H3btc), as a ligand, under pH-controlled hydrothermal conditions with nickel salts leads to the formation of a coordination polymer of {CsNi3(OH)(H2O)3[C6H3(CO2)3]2·3H2O}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, thus permitting the extent of deprotonation of the unsymmetrical ligand H3btc 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.
Minoura, Itsushi; Katayama, Eisaku; Sekimoto, Ken; Muto, Etsuko
2010-01-01
Abstract Various proteins are known to exhibit one-dimensional Brownian motion along charged rodlike polymers, such as microtubules (MTs), actin, and DNA. The electrostatic interaction between the proteins and the rodlike polymers appears to be crucial for one-dimensional Brownian motion, although the underlying mechanism has not been fully clarified. We examined the interactions of positively-charged nanoparticles composed of polyacrylamide gels with MTs. These hydrophilic nanoparticles bound to MTs and displayed one-dimensional Brownian motion in a charge-dependent manner, which indicates that nonspecific electrostatic interaction is sufficient for one-dimensional Brownian motion. The diffusion coefficient decreased exponentially with an increasing particle charge (with the exponent being 0.10 kBT per charge), whereas the duration of the interaction increased exponentially (exponent of 0.22 kBT per charge). These results can be explained semiquantitatively if one assumes that a particle repeats a cycle of binding to and movement along an MT until it finally dissociates from the MT. During the movement, a particle is still electrostatically constrained in the potential valley surrounding the MT. This entire process can be described by a three-state model analogous to the Michaelis-Menten scheme, in which the two parameters of the equilibrium constant between binding and movement, and the rate of dissociation from the MT, are derived as a function of the particle charge density. This study highlights the possibility that the weak binding interactions between proteins and rodlike polymers, e.g., MTs, are mediated by a similar, nonspecific charge-dependent mechanism. PMID:20409479
Magnons in one-dimensional k-component Fibonacci structures
NASA Astrophysics Data System (ADS)
Costa, C. H.; Vasconcelos, M. S.
2014-05-01
We have studied the magnon transmission through of one-dimensional magnonic k-component Fibonacci structures, where k different materials are arranged in accordance with the following substitution rule: Sn(k)=Sn-1(k)Sn-k(k) (n ?k=0,1,2,…), where Sn(k) is the nth stage of the sequence. The calculations were carried out in exchange dominated regime within the framework of the Heisenberg model and taking into account the RPA approximation. We have considered multilayers composed of simple cubic spin-S Heisenberg ferromagnets, and, by using the powerful transfer-matrix method, the spin wave transmission is obtained. It is demonstrated that the transmission coefficient has a rich and interesting magnonic pass- and stop-bands structures, which depends on the frequency of magnons and the k values.
Equilibrium properties of a one-dimensional kinetic system.
NASA Technical Reports Server (NTRS)
Williams, J. H.; Joyce, G.
1973-01-01
One-dimensional systems of N = 500 and 250 particles in equilibrium are numerically simulated utilizing the method of molecular dynamics. Periodic boundary conditions are imposed. The classical two-body interaction potential is short range, repulsive and has a corresponding finite force. The equations of state are determined for densities both less and greater than one. Corresponding theoretical isochores are determined from models based on nearest-neighbor interactions and on a truncated virial expansion, and a comparison is made with the experimental isochores. Time independent radial distributions are constructed numerically and discussed. A change of state from a solidlike state to a fluid-gas state based on the penetrability of the particles is predicted. The transition temperatures are estimated from the radial distribution functions and the nearest-neighbor model. Self-diffusion is observed and the corresponding constants are determined from the velocity autocorrelation functions.
Chaos in a one-dimensional compressible flow
Austin Gerig; Alfred Hubler
2007-01-24
We study the dynamics of a one-dimensional discrete flow with open boundaries - a series of moving point particles connected by ideal springs. These particles flow towards an inlet at constant velocity, pass into a region where they are free to move according to their nearest neighbor interactions, and then pass an outlet where they travel with a sinusoidally varying velocity. As the amplitude of the outlet oscillations is increased, we find that the resident time of particles in the chamber follows a bifurcating (Feigenbaum) route to chaos. This irregular dynamics may be related to the complex behavior of many particle discrete flows or is possibly a low-dimensional analogue of non-stationary flow in continuous systems.
Haldane gap in the quasi-one-dimensional nonlinear ? model
NASA Astrophysics Data System (ADS)
Sénéchal, David
1993-12-01
This work studies the appearance of a Haldane gap in quasi-one-dimensional antiferromagnets in the long-wavelength limit, via the nonlinear ? model. The mapping from the three-dimensional, integer-spin Heisenberg model to the nonlinear ? model is explained, taking into account two antiferromagnetic couplings: one along the chain axis (J) and one along the perpendicular planes (J?) of a cubic lattice. An implicit equation for the Haldane gap is derived, as a function of temperature and coupling ratio J?/J. Solutions to these equations show the existence of a critical coupling ratio beyond which a gap exists only above a transition temperature TN. The cutoff dependence of these results is discussed.
Model of a quasi-one-dimensional spin glass
NASA Astrophysics Data System (ADS)
Oreši?, M.; Pirc, R.
1993-02-01
We consider a system of linear chains of Ising spins with short-range nearest-neighbor ferromagnetic interactions of strength K along the chains, and with infinite-range random interchain interactions of a Sherrington-Kirkpatrick type. Also included in the model is a local Gaussian random field with variance ?. In the replica symmetric case, the system is mapped exactly on the one-dimensional Ising model in a random field and a recursion method for calculating the spin-correlation functions is developed. For ?=0, an analytic relation for freezing temperature Tf(K) is obtained. The replica-symmetric spin-glass phase is shown to be stable above the freezing temperature Tf(K,?), which is determined numerically.
Practical variational tomography for critical one-dimensional systems
NASA Astrophysics Data System (ADS)
Lee, Jong Yeon; Landon-Cardinal, Olivier
2015-06-01
We improve upon a recently introduced efficient quantum state reconstruction procedure targeted to states well approximated by the multiscale entanglement renormalization ansatz (MERA), e.g., ground states of critical models. We show how to numerically select a subset of experimentally accessible measurements which maximize information extraction about renormalized particles, thus dramatically reducing the required number of physical measurements. We numerically estimate the number of measurements required to characterize the ground state of the critical one-dimensional Ising (resp. XX) model and find that MERA tomography on 16-qubit (resp. 24-qubit) systems requires the same experimental effort as brute-force tomography on 8 qubits. We derive a bound computable from experimental data which certifies the distance between the experimental and reconstructed states.
Diffusive radiation in one-dimensional Langmuir turbulence.
Fleishman, G D; Toptygin, I N
2007-07-01
We calculate spectra of radiation produced by a relativistic particle in the presence of one-dimensional Langmuir turbulence which might be generated by a streaming instability in the plasma, in particular, in the shock front or at the shock-shock interactions. The shape of the radiation spectra is shown to depend sensitively on the angle between the particle velocity and electric field direction. The radiation spectrum in the case of exactly transverse particle motion is degenerate and similar to that of spatially uniform Langmuir oscillations. In the case of oblique propagation, the spectrum is more complex, it consists of a number of power-law regions and may contain a distinct high-frequency spectral peak. The emission process considered is relevant to various laboratory plasma settings and for astrophysical objects as gamma-ray bursts and collimated jets. PMID:17677604
Fractionalization of itinerant anyons in one dimensional chains
Didier Poilblanc; Matthias Troyer; Eddy Ardonne; Parsa Bonderson
2011-12-27
We construct models of interacting itinerant non-Abelian anyons moving along one-dimensional chains, focusing in particular on itinerant Ising anyon chains, and derive effective anyonic t-J models for the low energy sectors. Solving these models by exact diagonalization, we find a fractionalization of the anyons into charge and (non-Abelian) anyonic degrees of freedom -- a generalization of spin-charge separation of electrons which occurs in Luttinger liquids. A detailed description of the excitation spectrum by combining spectra for charge and anyonic sectors requires a subtle coupling between charge and anyonic excitations at the microscopic level (which we also find to be present in Luttinger liquids), despite the macroscopic fractionalization.
Kondo Polarons in a One-Dimensional Fermi Gas
Lamacraft, Austen [Department of Physics, University of Virginia, Charlottesville, Virginia 22904-4714 (United States)
2008-11-28
We consider the motion of a spin-1/2 impurity in a one-dimensional gas of spin-1/2 fermions. For antiferromagnetic interaction between the impurity and the fermions, the low temperature behavior of the system is governed by the two-channel Kondo effect, leading to the impurity becoming completely opaque to the spin excitations of the gas. As well as the known spectral signatures of the two-channel Kondo effect, we find that the low temperature mobility of the resulting 'Kondo polaron' takes the universal form {mu}{yields}3({Dirac_h}/2{pi})v{sub F}{sup 2}/2{pi}k{sub B}{sup 2}T{sup 2}, in sharp contrast to the spinless case where {mu}{proportional_to}T{sup -4}.
Entanglement in the one-dimensional Kondo necklace model
Saguia, A.; Sarandy, M.S. [CBPF, Centro Brasileiro de Pesquisas Fisicas, Rua Dr. Xavier Sigaud 150, Urca, Rio de Janeiro 22290-180 (Brazil); UERJ, Universidade do Estado do Rio de Janeiro, Rua Sao Francisco Xavier 524, Maracana, Rio de Janeiro 20550-013 (Brazil)
2003-01-01
We discuss the thermal and magnetic entanglement in the one-dimensional Kondo necklace model. First, we show how the entanglement naturally present at zero temperature is distributed among pairs of spins according to the strength of the two couplings of the chain, namely, the Kondo exchange interaction and the hopping energy. The effect of temperature and the presence of an external magnetic field are then investigated. We also discuss the adjustment of these variables in order to control the entanglement available in the system. In particular, it is indicated that there exists a critical magnetic field above which the entanglement undergoes a sharp variation, leading the ground state to a completely unentangled phase.
Strongly-Refractive One-Dimensional Photonic Crystal Prisms
NASA Technical Reports Server (NTRS)
Ting, David Z. (Inventor)
2004-01-01
One-dimensional (1D) photonic crystal prisms can separate a beam of polychromatic electromagnetic waves into constituent wavelength components and can utilize unconventional refraction properties for wavelength dispersion over significant portions of an entire photonic band rather than just near the band edges outside the photonic band gaps. Using a ID photonic crystal simplifies the design and fabrication process and allows the use of larger feature sizes. The prism geometry broadens the useful wavelength range, enables better optical transmission, and exhibits angular dependence on wavelength with reduced non-linearity. The properties of the 1 D photonic crystal prism can be tuned by varying design parameters such as incidence angle, exit surface angle, and layer widths. The ID photonic crystal prism can be fabricated in a planar process, and can be used as optical integrated circuit elements.
Resonant scattering induced thermopower in one-dimensional disordered systems
NASA Astrophysics Data System (ADS)
Müller, Daniel; Smit, Wilbert J.; Sigrist, Manfred
2015-05-01
This study analyzes thermoelectric properties of a one-dimensional random conductor which shows localization effects and simultaneously includes resonant scatterers yielding sharp conductance resonances. These sharp features give rise to a distinct behavior of the Seebeck coefficient in finite systems and incorporate the degree of localization as a means to enhance thermoelectric performance, in principle. The model for noninteracting electrons is discussed within the Landauer-Büttiker formalism such that analytical treatment is possible for a wide range of properties, if a special averaging scheme is applied. The approximations in the averaging procedure are tested with numerical evaluations showing good qualitative agreement, with some limited quantitative disagreement. The validity of low-temperature Mott's formula is determined and a good approximation is developed for the intermediate temperature range. In both regimes the intricate interplay between Anderson localization due to disorder and conductance resonances of the disorder potential is analyzed.
One-dimensional photonic crystal fishbone hybrid nanocavity with nanoposts
NASA Astrophysics Data System (ADS)
Lu, Tsan-Wen; Lin, Pin-Tso; Lee, Po-Tsung
2014-05-01
We propose and investigate a one-dimensional photonic crystal (PhC) fishbone (FB) hybrid nanocavity lying on silver substrate with a horizontal air slot. With very few PhC periods, the confined transverse-magnetic, TM10 hybrid mode concentrated within the air slot shows high quality factor over effective mode volume ratio larger than 105?-3. Most importantly, this FB hybrid nanocavity allows formation of low-index nanoposts within the air slot without significantly affecting the mode properties. These nanoposts guarantee the structural stabilities under different environmental perturbations. Furthermore, capabilities of our proposed design in serving as optical sensors and tweezers for bio-sized nanoparticles are also investigated.
Quantum Fields bounded by one dimensional crystal plates
J. M. Munoz-Castaneda; M. Bordag
2011-04-27
We get deeper understanding of the role played by boundary conditions in quantum field theory, by studying the structure of a scalar massless quantum field theory bounded by two one dimensional planar crystal plates. The system can also be understood as a massless scalar confined to propagate in the surface of a finite cylinder. We classify the most general type of regular behaved boundary conditions that the quantum field can satisfy, in accordance with the unitarity principle of quantum field theory. Also, we characterize the frequency spectrum for each quantum field theory, by computing the holomorphic spectral function. The spectral function is the starting point to compute the Casimir energy as a global function over the space of allowed boundary conditions for the quantum field theory.
Quantum quenches and thermalization in one-dimensional fermionic systems
NASA Astrophysics Data System (ADS)
Rigol, Marcos
2009-11-01
We study the dynamics and thermalization of strongly correlated fermions in finite one-dimensional lattices after a quantum quench. Our calculations are performed using exact diagonalization. We focus on one- and two-body observables such as the momentum distribution function [n(k)] and the density-density structure factor [N(k)] , respectively, and study the effects of approaching an integrable point. We show that while the relaxation dynamics and thermalization of N(k) for fermions is very similar to the one of hardcore bosons, the behavior of n(k) is distinctively different. The latter observable exhibits a slower relaxation dynamics in fermionic systems. We identify the origin of this behavior, which is related to the off-diagonal matrix elements of n(k) in the basis of the eigenstates of the Hamiltonian. More generally, we find that thermalization occurs far away from integrability and that it breaks down as one approaches the integrable point.
Microwave properties of nonlinear one-dimensional quasiperiodic photonic crystals
NASA Astrophysics Data System (ADS)
Trabelsi, Y.; Kanzari, M.
2012-06-01
The nonlinear properties of quasi-periodic photonic crystals based on the Thue-Morse and Fibonacci sequence are investigated. We address the transmission properties of waves through one dimensional symmetric Fibonacci, and Thue-Morse system i.e., a quasiperiodic structure made up of two different dielectric materials (Rogers and air), in quarter wavelength condition, presenting in the one directions. The microwave spectra are calculated by using transfer matrix method in normal incidence geometry. In our results we present the self-similar features of the spectra and we also present the microwave properties through a return map of the transmission coefficients. We extract powerfully the band gaps of quasi-periodic multilayered structures, called `pseudo band gaps' often contain resonant states, which can be considered as a manifestation of numerous defects distributed along the structure. Taken together, the above two properties provide favorable conditions for the design of an all-microwave reflector.
Source of Relaxation in the One Dimensional Gravitating System
NASA Astrophysics Data System (ADS)
Miller, Bruce
1996-05-01
Recent numerical experiments suggest that the one dimensional system consisting of N parallel mass sheets relaxes on two time scales: a rapid violent phase with duration of order T (a typical system crossing time) resulting in a quasi-equilibrium (QE) state followed by (2) a succession of QE states leading finally to thermal equilibrium. Within each QE state fluctuations relax on a time scale of order NT while complete thermalization occurs in about 10^4NT. Here I show that both time scales can be explained within the context of a diffusion model developed by the author and K. Yawn* (K. R. Yawn and B. N. Miller, Phys. Rev. E v.52, p. 3390 (1995).) specifically for this system.
Loschmidt echo in one-dimensional interacting Bose gases
Lelas, K.; Seva, T.; Buljan, H. [Faculty of Electrical Engineering Mechanical Engineering and Naval Architecture, University of Split, Rudjera Boskovica BB, 21000 Split (Croatia); Department of Physics, University of Zagreb, Bijenicka c. 32, 10000 Zagreb (Croatia)
2011-12-15
We explore Loschmidt echo in two regimes of one-dimensional interacting Bose gases: the strongly interacting Tonks-Girardeau (TG) regime, and the weakly interacting mean-field regime. We find that the Loschmidt echo of a TG gas decays as a Gaussian when small (random and time independent) perturbations are added to the Hamiltonian. The exponent is proportional to the number of particles and the magnitude of a small perturbation squared. In the mean-field regime the Loschmidt echo shows richer behavior: it decays faster for larger nonlinearity, and the decay becomes more abrupt as the nonlinearity increases; it can be very sensitive to the particular realization of the noise potential, especially for relatively small nonlinearities.
One-dimensional hybrid nanostructures for heterogeneous photocatalysis and photoelectrocatalysis.
Xiao, Fang-Xing; Miao, Jianwei; Tao, Hua Bing; Hung, Sung-Fu; Wang, Hsin-Yi; Yang, Hong Bin; Chen, Jiazang; Chen, Rong; Liu, Bin
2015-05-01
Semiconductor-based photocatalysis and photoelectrocatalysis have received considerable attention as alternative approaches for solar energy harvesting and storage. The photocatalytic or photoelectrocatalytic performance of a semiconductor is closely related to the design of the semiconductor at the nanoscale. Among various nanostructures, one-dimensional (1D) nanostructured photocatalysts and photoelectrodes have attracted increasing interest owing to their unique optical, structural, and electronic advantages. In this article, a comprehensive review of the current research efforts towards the development of 1D semiconductor nanomaterials for heterogeneous photocatalysis and photoelectrocatalysis is provided and, in particular, a discussion of how to overcome the challenges for achieving full potential of 1D nanostructures is presented. It is anticipated that this review will afford enriched information on the rational exploration of the structural and electronic properties of 1D semiconductor nanostructures for achieving more efficient 1D nanostructure-based photocatalysts and photoelectrodes for high-efficiency solar energy conversion. PMID:25641821
One-dimensional quantum walk with unitary noise
Shapira, Daniel; Biham, Ofer; Bracken, A.J.; Hackett, Michelle [Racah Institute of Physics, Hebrew University, Jerusalem, 91904 (Israel); Department of Mathematics, University of Queensland, Brisbane, Queensland 4072 (Australia)
2003-12-01
The effect of unitary noise on the discrete one-dimensional quantum walk is studied using computer simulations. For the noiseless quantum walk, starting at the origin (n=0) at time t=0, the position distribution P{sub t}(n) at time t is very different from the Gaussian distribution obtained for the classical random walk. Furthermore, its standard deviation, {sigma}(t) scales as {sigma}(t){approx}t, unlike the classical random walk for which {sigma}(t){approx}{radical}(t). It is shown that when the quantum walk is exposed to unitary noise, it exhibits a crossover from quantum behavior for short times to classical-like behavior for long times. The crossover time is found to be T{approx}{alpha}{sup -2}, where {alpha} is the standard deviation of the noise.
One-dimensional Hybrid Approach to Extensive Air Shower Simulation
T. Bergmann; R. Engel; D. Heck; N. N. Kalmykov; S. Ostapchenko; T. Pierog; T. Thouw; K. Werner
2006-06-22
An efficient scheme for one-dimensional extensive air shower simulation and its implementation in the program CONEX are presented. Explicit Monte Carlo simulation of the high-energy part of hadronic and electromagnetic cascades in the atmosphere is combined with a numeric solution of cascade equations for smaller energy sub-showers to obtain accurate shower predictions. The developed scheme allows us to calculate not only observables related to the number of particles (shower size) but also ionization energy deposit profiles which are needed for the interpretation of data of experiments employing the fluorescence light technique. We discuss in detail the basic algorithms developed and illustrate the power of the method. It is shown that Monte Carlo, numerical, and hybrid air shower calculations give consistent results which agree very well with those obtained within the CORSIKA program.
Properties of surface modes in one dimensional plasma photonic crystals
NASA Astrophysics Data System (ADS)
Shukla, S.; Prasad, S.; Singh, V.
2015-02-01
Properties of surface modes supported at the interface of air and a semi-infinite one dimensional plasma photonic crystal are analyzed. The surface mode equation is obtained by using transfer matrix method and applying continuity conditions of electric fields and its derivatives at the interface. It is observed that with increase in the width of cap layer, frequencies of surface modes are shifted towards lower frequency side, whereas increase in tangential component of wave-vector increases the mode frequency and total energy carried by the surface modes. With increase in plasma frequency, surface modes are found to shift towards higher frequency side. The group velocity along interface is found to control by cap layer thickness.
One-dimensional photonic crystal fishbone hybrid nanocavity with nanoposts
Lu, Tsan-Wen; Lin, Pin-Tso; Lee, Po-Tsung, E-mail: potsung@mail.nctu.edu.tw [Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University, Rm. 413 CPT Building, 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan (China)
2014-05-12
We propose and investigate a one-dimensional photonic crystal (PhC) fishbone (FB) hybrid nanocavity lying on silver substrate with a horizontal air slot. With very few PhC periods, the confined transverse-magnetic, TM{sub 10} hybrid mode concentrated within the air slot shows high quality factor over effective mode volume ratio larger than 10{sup 5}?{sup ?3}. Most importantly, this FB hybrid nanocavity allows formation of low-index nanoposts within the air slot without significantly affecting the mode properties. These nanoposts guarantee the structural stabilities under different environmental perturbations. Furthermore, capabilities of our proposed design in serving as optical sensors and tweezers for bio-sized nanoparticles are also investigated.
Experiment and simulation on one-dimensional plasma photonic crystals
Zhang, Lin; Ouyang, Ji-Ting, E-mail: jtouyang@bit.edu.cn [School of Physics, Beijing Institute of Technology, Beijing 100081 (China)
2014-10-15
The transmission characteristics of microwaves passing through one-dimensional plasma photonic crystals (PPCs) have been investigated by experiment and simulation. The PPCs were formed by a series of discharge tubes filled with argon at 5?Torr that the plasma density in tubes can be varied by adjusting the discharge current. The transmittance of X-band microwaves through the crystal structure was measured under different discharge currents and geometrical parameters. The finite-different time-domain method was employed to analyze the detailed properties of the microwaves propagation. The results show that there exist bandgaps when the plasma is turned on. The properties of bandgaps depend on the plasma density and the geometrical parameters of the PPCs structure. The PPCs can perform as dynamical band-stop filter to control the transmission of microwaves within a wide frequency range.
Luttinger-liquid behavior of one-dimensional 3He
NASA Astrophysics Data System (ADS)
Astrakharchik, G. E.; Boronat, J.
2014-12-01
The ground-state properties of one-dimensional 3He are studied using quantum Monte Carlo methods. The equation of state is calculated in a wide range of physically relevant densities and is well interpolated by a power-series fit. The Luttinger liquid theory is found to describe the long-range properties of the correlation functions. The density dependence of the Luttinger parameter is explicitly found, and interestingly it shows a nonmonotonic behavior. Depending on the density, the static structure factor can be a smooth function of the momentum or might contain a peak of a finite or infinite height. Although no phase transitions are present in the system, we identify a number of physically different regimes, including an ideal Fermi gas, a "Bose gas." a "super-Tonks-Girardeau" regime, and a "quasicrystal." The obtained results are applicable to unpolarized, partially, or fully polarized 3He.
Characterization of one-dimensional lasing in semiconductor disordered nanopowders.
Rafiee, Peyman; Haghighat, Gholamhossein; Ahmadi, Vahid
2013-02-01
In this paper, we present characteristics of one-dimensional ZnO-based random lasers by using a time-domain traveling-wave model. The results reveal that by increasing pump intensity, at first the number of laser modes is increased, and then it gets saturated. Also, output intensity shows that by increasing pump pulse width at a fixed pump intensity, laser modes are made to appear; at first, by raising pump pulse width, more laser modes appear, and then the intensity of the output spectrum is increased. Additionally, we show that by nonuniform pumping, a single-mode laser can be achieved. Through investigation of the nanopowder's average size, we show that the output spectrum has its highest intensity and the sharpest laser modes for average nanopowder sizes less than 100 nm. Moreover, the results show that by decreasing pump area, lasing threshold is inclined. PMID:23385903
Majorana fermion exchange in strictly one-dimensional structures
NASA Astrophysics Data System (ADS)
Chiu, Ching-Kai; Vazifeh, M. M.; Franz, M.
2015-04-01
It is generally thought that the adiabatic exchange of two identical particles is impossible in one spatial dimension. Here we describe a simple protocol that permits the adiabatic exchange of two Majorana fermions in a one-dimensional topological superconductor wire. The exchange relies on the concept of “Majorana shuttle” whereby a ? domain wall in the superconducting order parameter which hosts a pair of ancillary majoranas delivers one zero mode across the wire while the other one tunnels in the opposite direction. The method requires some tuning of parameters and does not, therefore, enjoy full topological protection. The resulting exchange statistics, however, remain non-Abelian for a wide range of parameters that characterize the exchange.
Users manual for a one-dimensional Lagrangian transport model
Schoellhamer, D.H.; Jobson, H.E.
1986-01-01
A Users Manual for the Lagrangian Transport Model (LTM) is presented. The LTM uses Lagrangian calculations that are based on a reference frame moving with the river flow. The Lagrangian reference frame eliminates the need to numerically solve the convective term of the convection-diffusion equation and provides significant numerical advantages over the more commonly used Eulerian reference frame. When properly applied, the LTM can simulate riverine transport and decay processes within the accuracy required by most water quality studies. The LTM is applicable to steady or unsteady one-dimensional unidirectional flows in fixed channels with tributary and lateral inflows. Application of the LTM is relatively simple and optional capabilities improve the model 's convenience. Appendices give file formats and three example LTM applications that include the incorporation of the QUAL II water quality model 's reaction kinetics into the LTM. (Author 's abstract)
One-Dimensional Time to Explosion (Thermal Sensitivity) of ANPZ
Hsu, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hust, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McClelland, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gresshoff, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
2014-11-12
Incidents caused by fire and combat operations can heat energetic materials that may lead to thermal explosion and result in structural damage and casualty. Some explosives may thermally explode at fairly low temperatures (< 100 C) and the violence from thermal explosion may cause a significant damage. Thus it is important to understand the response of energetic materials to thermal insults. The One Dimensional Time to Explosion (ODTX) system at the Lawrence Livermore National Laboratory has been used for decades to measure times to explosion, threshold thermal explosion temperature, and determine kinetic parameters of energetic materials. Samples of different configurations (pressed part, powder, paste, and liquid) can be tested in the system. The ODTX testing can also provide useful data for assessing the thermal explosion violence of energetic materials. This report summarizes the recent ODTX experimental data and modeling results for 2,6-diamino-3,5-dintropyrazine (ANPZ).
Study on pile drivability with one dimensional wave propagation theory.
Chen, Ren-peng; Wang, Shi-fang; Chen, Yun-min
2003-01-01
Pile drivability is a key problem during the stage of design and construction installation of pile foundations. The solution to the one dimensional wave equation was used to determine the impact force at the top of a concrete pile for a given ram mass, cushion stiffness, and pile impedance. The kinematic equation of pile toe was established and solved based on wave equation theory. The movements of the pile top and pile toe were presented, which clearly showed the dynamic displacement, including rebound and penetration of pile top and toe. A parametric study was made with a full range of practical values of ram weight, cushion stiffness, drop eight, and pile impedance. Suggestions for optimizing the parameters were also presented. Comparisons between the results obtained by the present solution and in-situ measurements indicated the reliability and validity of the method. PMID:14566984
Erosion by a one-dimensional random walk
NASA Astrophysics Data System (ADS)
Chisholm, Rebecca H.; Hughes, Barry D.; Landman, Kerry A.
2014-08-01
We consider a model introduced by Baker et al. [Phys. Rev. E 88, 042113 (2013), 10.1103/PhysRevE.88.042113] of a single lattice random walker moving on a domain of allowed sites, surrounded by blocked sites. The walker enlarges the allowed domain by eroding the boundary at its random encounters with blocked boundary sites: attempts to step onto blocked sites succeed with a given probability and convert these sites to allowed sites. The model interpolates continuously between the Pólya random walker on the one-dimensional lattice and a "blind" walker who attempts freely, but always aborts, moves to blocked sites. We obtain some exact results about the walker's location and the rate of erosion.
Strongly interacting quantum gases in one-dimensional traps
NASA Astrophysics Data System (ADS)
Yang, Li; Guan, Liming; Pu, Han
2015-04-01
Under second-order degenerate perturbation theory, we show that the physics of N particles with arbitrary spin confined in a one-dimensional trap in the strongly interacting regime can be described by superexchange interaction. An effective spin-chain Hamiltonian (non-translationally-invariant Sutherland model) can be constructed from this procedure. For spin-1/2 particles, this model reduces to the non-translationally-invariant Heisenberg model, where a transition between Heisenberg antiferromagnetic (AFM) and ferromagnetic (FM) states is expected to occur when the interaction strength is tuned from the strongly repulsive to the strongly attractive limit. We show that the FM and the AFM states can be distinguished by two different methods: the first is based on their distinct responses to a spin-dependent magnetic gradient, and the second is based on their distinct momentum distributions. We confirm the validity of the spin-chain model by comparison with results obtained from several unbiased techniques.
Feedback-induced oscillations in one-dimensional colloidal transport
Ken Lichtner; Andrey Pototsky; Sabine H. L. Klapp
2012-09-05
We investigate a driven, one-dimensional system of colloidal particles in a periodically currogated narrow channel subject to a time-delayed feedback control. Our goal is to identify conditions under which the control induces oscillatory, time-periodic states. The investigations are based on the Fokker-Planck equation involving the density distribution of the system. First, by using the numerical continuation technique, we determine the linear stability of a stationary density. Second, the nonlinear regimes are analyzed by studying numerically the temporal evolution of the first moment of the density distribution. In this way we construct a bifurcation diagram revealing the nature of the instability. Apart from the case of a system with periodic boundary conditions, we also consider a microchannel of finite length. Finally, we study the influence of (repulsive) particle interactions based on Dynamical Density Functional Theory (DDFT).
One-dimensional modeling of steam injection in tar sands
Chen, C.S.; Hutchinson, H.L.
1983-01-01
A one-dimensional numeric model of steam injection was developed and used to simulate experimental steam and hot water injection in the Asphalt Ridge tar sands. The model described a 3-phase flow system of water, steam and oil with interphase mass transfer of water. The mass and energy balance equations were solved simultaneously by a semi-implicit Sequential Solution method. The results of the linear numeric simulator showed moderate agreement with the observed results from the steam and hot water injection experiments. The simulator predicted that (1) changes in relative permeability, thermal expansion coefficient of oil and oil viscosity are important factors affecting oil recovery from tar sands, and (2) the oil response time is decreased with increasing steam injection rate and quality, and is decreased by reducing steam injection temperature. 22 references.
One-dimensional plasma photonic crystals with sinusoidal densities
Qi, L., E-mail: qilimei1204@163.com; Shang, L.; Zhang, S. [College of Physics and Engineering, Qufu Normal University, No. 57, West Jingxuan Road, Qufu 273165 (China)] [College of Physics and Engineering, Qufu Normal University, No. 57, West Jingxuan Road, Qufu 273165 (China)
2014-01-15
Properties of electromagnetic waves with normal and oblique incidence have been studied for one-dimensional plasma layers with sinusoidal densities. Wave transmittance as a function of wave frequency exhibits photonic band gaps characteristic of photonic crystals. For periodic structures, increasing collision frequency is demonstrated to lead to greater absorption, increasing the modulation factor enlarges the gap width, and increasing incidence angle can change the gap locations of the two polarizations. If a defect layer is introduced by inserting a new plasma layer in the center, a defect mode may appear within the gap. Periodic number, collision frequency, and modulation factor can affect magnitude of the defect mode. The incidence angle enables the frequency to be tuned. Defect layer thickness affects both frequency and number of defect modes. These results may provide theoretical guidance in designing tunable narrow-band filters.
One-dimensional quantum walks with absorbing boundaries
Eric Bach; Susan Coppersmith; Marcel Paz Goldschen; Robert Joynt; John Watrous
2002-08-12
In this paper we analyze the behavior of quantum random walks. In particular we present several new results for the absorption probabilities in systems with both one and two absorbing walls for the one-dimensional case. We compute these probabilites both by employing generating functions and by use of an eigenfunction approach. The generating function method is used to determine some simple properties of the walks we consider, but appears to have limitations. The eigenfunction approach works by relating the problem of absorption to a unitary problem that has identical dynamics inside a certain domain, and can be used to compute several additional interesting properties, such as the time dependence of absorption. The eigenfunction method has the distinct advantage that it can be extended to arbitrary dimensionality. We outline the solution of the absorption probability problem of a (d-1)-dimensional wall in a d-dimensional space.
One-dimensional quantum walks with absorbing boundaries
Bach, E; Paz-Goldschen, M; Joynt, R; Watrous, J; Bach, Eric; Coppersmith, Susan; Goldschen, Marcel Paz; Joynt, Robert; Watrous, John
2002-01-01
In this paper we analyze the behavior of quantum random walks. In particular we present several new results for the absorption probabilities in systems with both one and two absorbing walls for the one-dimensional case. We compute these probabilites both by employing generating functions and by use of an eigenfunction approach. The generating function method is used to determine some simple properties of the walks we consider, but appears to have limitations. The eigenfunction approach works by relating the problem of absorption to a unitary problem that has identical dynamics inside a certain domain, and can be used to compute several additional interesting properties, such as the time dependence of absorption. The eigenfunction method has the distinct advantage that it can be extended to arbitrary dimensionality. We outline the solution of the absorption probability problem of a (d-1)-dimensional wall in a d-dimensional space.
A Reduced Order, One Dimensional Model of Joint Response
DOHNER,JEFFREY L.
2000-11-06
As a joint is loaded, the tangent stiffness of the joint reduces due to slip at interfaces. This stiffness reduction continues until the direction of the applied load is reversed or the total interface slips. Total interface slippage in joints is called macro-slip. For joints not undergoing macro-slip, when load reversal occurs the tangent stiffness immediately rebounds to its maximum value. This occurs due to stiction effects at the interface. Thus, for periodic loads, a softening and rebound hardening cycle is produced which defines a hysteretic, energy absorbing trajectory. For many jointed sub-structures, this hysteretic trajectory can be approximated using simple polynomial representations. This allows for complex joint substructures to be represented using simple non-linear models. In this paper a simple one dimensional model is discussed.
Dynamics and Thermalisation in Correlated One-Dimensional Lattice Systems
NASA Astrophysics Data System (ADS)
Rigol, Marcos
2013-02-01
We review exact approaches and recent results related to the relaxation dynamics and description after relaxation of various one-dimensional lattice systems of hard-core bosons after a sudden quench. We first analyse the integrable case, where the combination of analytical insights and computational techniques enable the study of large system sizes. Thermalisation does not occur in this regime. However, after relaxation, observables can be described by a generalisation of the Gibbs ensemble. We then utilise full exact diagonalisation to study what happens as integrability is broken. We show that thermalisation does occur in finite nonintegrable systems provided that they are sufficiently far away from the integrable point. We argue that the onset of thermalisation can be understood in terms of the eigenstate-thermalisation hypothesis.
Fomina, Irina, E-mail: fomina@igic.ras.ru [N.S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, GSP-1 (Russian Federation); Dobrokhotova, Zhanna; Aleksandrov, Grygory [N.S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, GSP-1 (Russian Federation); Emelina, Anna; Bykov, Mikhail [Department of Chemistry, M.V. Lomonosov Moscow State University, Leninskie Gory 1/3, 119991 Moscow, GSP-1 (Russian Federation); Malkerova, Irina [N.S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, GSP-1 (Russian Federation); Bogomyakov, Artem [International Tomography Center, Siberian Branch of the Russian Academy of Sciences, Institutskaya Str. 3a, 630090 Novosibirsk (Russian Federation); Puntus, Lada [Kotel'nikov Institute of Radioengineering and Electronics, Russian Academy of Sciences, Mokhovaya Str. 11-7, 125009 Moscow (Russian Federation); Novotortsev, Vladimir; Eremenko, Igor [N.S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, GSP-1 (Russian Federation)
2012-01-15
The new 1D coordination polymer {l_brace}Tm(Piv){sub 3{r_brace}n} (1), where Piv=OOCBu{sup t-}, was synthesized in high yield (>95%) by the reaction of thulium acetate with pivalic acid in air at 100 Degree-Sign S. According to the X-ray diffraction data, the metal atoms in compound 1 are in an octahedral ligand environment unusual for lanthanides. The magnetic and luminescence properties of polymer 1, it's the solid-phase thermal decomposition in air and under argon, and the thermal behavior in the temperature range of -50 Horizontal-Ellipsis +50 Degree-Sign S were investigated. The vaporization process of complex 1 was studied by the Knudsen effusion method combined with mass-spectrometric analysis of the gas-phase composition in the temperature range of 570-680 K. - Graphical Abstract: Novel 1D coordination polymer {l_brace}Tm(Piv){sub 3{r_brace}n} was synthesized and studied by X-ray diffraction. The magnetic, luminescence properties, the thermal behavior and the volatility for the compound {l_brace}Tm(Piv){sub 3{r_brace}n} were investigated. Black-Small-Square Highlights: Black-Right-Pointing-Pointer We synthesized the coordination polymer {l_brace}Tm(Piv){sub 3{r_brace}n}. Black-Right-Pointing-Pointer Tm atoms in polymer have the coordination number 6. Black-Right-Pointing-Pointer Polymer exhibits blue-color emission at room temperature. Black-Right-Pointing-Pointer Polymer shows high thermal stability and volatility. Black-Right-Pointing-Pointer Polymer has no phase transitions in the range of -50 Horizontal-Ellipsis +50 Degree-Sign S.
Amarante, Tatiana R; Neves, Patrícia; Valente, Anabela A; Paz, Filipe A Almeida; Fitch, Andrew N; Pillinger, Martyn; Gonçalves, Isabel S
2013-04-15
The reaction of MoO3, 2,2'-bipyridine-5,5-dicarboxylic acid (H2bpdc), water, and dimethylformamide in the mole ratio 1:1:1730:130 at 150 °C for 3 days in a rotating Teflon-lined digestion bomb leads to the isolation of the molybdenum oxide/bipyridinedicarboxylate hybrid material (DMA)[MoO3(Hbpdc)]·nH2O (1) (DMA = dimethylammonium). Compound 1 was characterized by scanning electron microscopy, FT-IR and (13)C{(1)H} CP MAS NMR spectroscopies, and elemental and thermogravimetric analyses. The solid state structure of 1 was solved and refined through Rietveld analysis of high resolution synchrotron X-ray powder diffraction data in conjunction with information derived from the above techniques. The material, crystallizing in the noncentrosymmetric monoclinic space group Pc, is composed of an anionic one-dimensional organic-inorganic hybrid polymer, ?(1)[MoO3(Hbpdc)](-), formed by corner-sharing distorted {MoO4N2} octahedra, which cocrystallizes with charge-balancing DMA(+) cations and one water molecule per metal center. In the crystal structure of 1, the close packing of individual anionic polymers, DMA(+) cations, and water molecules is mediated by a series of supramolecular contacts, namely strong (O-H···O, N(+)-H···O(-)) and weak (C-H···O) hydrogen bonding interactions, and ?-? contacts involving adjacent coordinated Hbpdc(-) ligands. The catalytic potential of 1 was investigated in the epoxidation reactions of the bioderived olefins methyl oleate (Ole) and DL-limonene (Lim) using tert-butylhydroperoxide (TBHP) as the oxygen donor and 1,2-dichloroethane (DCE) or (trifluoromethyl)benzene (BTF) as cosolvent, at 55 or 75 °C. Under these conditions, 1 acts as a source of active soluble species, leading to epoxide yields of up to 98% for methyl 9,10-epoxystearate (BTF, 75 °C, 100% conversion of Ole) and 89% for 1,2-epoxy-p-menth-8-ene (DCE, 55 °C, 95% conversion of Lim). Catalytic systems employing the ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide as solvent could be effectively recycled. PMID:23531277
Konarev, Dmitri V; Khasanov, Salavat S; Nakano, Yoshiaki; Otsuka, Akihiro; Yamochi, Hideki; Saito, Gunzi; Lyubovskaya, Rimma N
2014-11-17
Coordination nickel-bridged fullerene polymer [{Ni(Me3P)2}(?-?(2),?(2)-C60)]? (1) has been obtained via reduction of a Ni(II)(Me3P)2Cl2 and C60 mixture. Each nickel atom is linked in the polymer with two fullerene units by ?(2)-type Ni-C(C60) bonds of 2.087(8)-2.149(8) Å length. Nickel atoms are coordinated to the 6-6 bonds of C60 as well as two trimethylphosphine ligands to form a four-coordinated environment around the metal centers. Fullerene cages approach very close to each other in the polymer with a 9.693(3) Å interfullerene center-to-center distance, and two short interfullerene C-C contacts of 2.923(7) Å length are formed. Polymer chains are densely packed in a crystal with interfullerene center-to-center distances between fullerenes from neighboring polymer chains of 9.933(3) Å and multiple interfullerene C···C contacts. As a result, three-dimensional dense fullerene packing is formed in 1. According to optical and electron paramagnetic resonance spectra, fullerenes are neutral in 1 and nickel atoms have a zerovalent state with a diamagnetic d(10) electron configuration. The density functional theory calculations prove the diamagnetic state of the polymer with a singlet-triplet gap wider than 1.37 eV. PMID:25369115
Zhang Shuai; Cao Yanning [Department of Chemistry, Fuzhou University, Fuzhou, Fujian 350002 (China); Zhang Hanhui [Department of Chemistry, Fuzhou University, Fuzhou, Fujian 350002 (China); State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China)], E-mail: zhanghh1840@hotmail.com; Chai Xiaochuan; Chen Yiping [Department of Chemistry, Fuzhou University, Fuzhou, Fujian 350002 (China)
2008-03-15
Two copper helical coordination polymers, [Cu(2-pc)(3-pc)]{sub n}1 and [Cu(2-pc)(4-pc)]{sub n}2 (2-pc=2-pyridine carboxylate, 3-pc=3-pyridine carboxylate, 4-pc=4-pyridine carboxylate) have been hydrothermally synthesized directly from pyridine carboxylic acids and copper nitrate. The crystal structure were determined by single-crystal X-ray diffraction with the following data: compound 1, orthorhombic, P2{sub 1}2{sub 1}2{sub 1}, a=6.591(3) A, b=8.692(5) A, c=20.548(9) A, V=1177.2(9) A{sup 3}, Z=4; compound 2, orthorhombic, Pna2{sub 1}, a=21.160(10) A, b=9.095(5) A, c=6.401(3) A, V=1231.9(11) A{sup 3}, Z=4. The acentric three-dimensional (3D) framework of 1 is constructed from right-handed helical Cu(2-pc) chains and left-handed Cu(3-pc) helices. As for 2, Cu(2-pc) helical chains, in which left- and right-handed helices are coexisting, and Cu(4-pc) zigzag chains combined together to form acentric 3D architecture of 2 as well. Additionally, besides general spectral characterization, we first introduce generalized 2D correlation spectroscopy to explore the coordination polymers and ascertain the stretching vibration location of carboxylate groups of compounds 1 and 2. -- Abstract: Two copper helical coordination polymers, [Cu(2-pc)(3-pc)]{sub n}1 and [Cu(2-pc)(4-pc)]{sub n}2 have been obtained by hydrothermal synthesis. Both two compounds crystallized in non-centrosymmetric space groups, P2{sub 1}2{sub 1}2{sub 1} and Pna2{sub 1}, respectively. The 3D framework of 1 is constructed from right-handed helical Cu(2-pc) chains and left-handed Cu(3-pc) helices. As for 2, Cu(2-pc) helical chains, in which left- and right-handed helices are coexisting, and Cu(4-pc) zigzag chains combined together to form 3D architecture of 2 as well.
Ar?c?, Mürsel [Department of Chemistry, Faculty of Arts and Sciences, Eski?ehir Osmangazi University, 26480 Eski?ehir (Turkey); Ye?ilel, Okan Zafer, E-mail: yesilel@ogu.edu.tr [Department of Chemistry, Faculty of Arts and Sciences, Eski?ehir Osmangazi University, 26480 Eski?ehir (Turkey); Keskin, Seda [Department of Chemical and Biological Engineering, Koç University, ?stanbul (Turkey); ?ahin, Onur [Scientific and Technological Research Application and Research Center, Sinop University, 57010 Sinop (Turkey)
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 complex 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.
Phase Space Description of Localization in Disordered One-Dimensional Systems
NASA Astrophysics Data System (ADS)
Wo?oszyn, M.; Spisak, B. J.; Maksymowicz, A. Z.
2006-10-01
The degree of electronic localization in disordered one-dimensional systems is discussed. The model is simplified to a set of Dirac ?-like functions used for the potential in the Schrödinger equation and calculations are carried out for the ground state. The disorder of topological character is introduced by the random shifts of the potential peaks. For comparison, we also discuss two aperiodic systems of the potential peaks: Thue-Morse and Fibonacci sequences. The localization, both in the momentum and the real space, is analyzed for different disorder strengths and sizes of the system. We calculate the localization length, and additionally we express the localization effects in terms of the inverse participation function and also by means of the Husimi quasi-classical distribution function in the phase space of the electron (position, momentum) coordinate system. We present the influence of disorder generated by the random and aperiodic sequences of potential on the energy spectrum.
One dimensional scattering of a two body interacting system by an infinite wall
A. M. Moro; J. A. Caballero; J. Gomez-Camacho
2010-10-24
The one-dimensional scattering of a two body interacting system by an infinite wall is studied in a quantum-mechanical framework. This problem contains some of the dynamical features present in the collision of atomic, molecular and nuclear systems. The scattering problem is solved exactly, for the case of a harmonic interaction between the fragments. The exact result is used to assess the validity of two different approximations to the scattering process. The adiabatic approximation, which considers that the relative co-ordinate is frozen during the scattering process, is found to be inadequate for this problem. The uncorrelated scattering approximation, which neglects the correlation between the fragments, gives results in accordance with the exact calculations when the scattering energy is high compared to the oscillator parameter.
Characterizing the Haldane phase in quasi-one-dimensional spin-1 Heisenberg antiferromagnets
NASA Astrophysics Data System (ADS)
Wierschem, Keola; Sengupta, Pinaki
2014-12-01
We review the basic properties of the Haldane phase in spin-1 Heisenberg antiferromagnetic chains, including its persistence in quasi-one-dimensional (Q1D) geometries. Using large-scale numerical simulations, we map out the phase diagram for a realistic model applicable to experimental Haldane compounds. We also investigate the effect of different chain coupling geometries and confirm a general mean-field universality of the critical coupling times the coordination number of the lattice. Inspired by recent developments in the characterization of symmetry protected topological (SPT) states, of which the Haldane phase of the spin-1 Heisenberg antiferromagnetic chain is a preeminent example, we provide direct evidence that the Q1D Haldane phase is indeed a nontrivial SPT state.
Moment-Preserving SN Discretizations for the One-Dimensional Fokker-Planck Equation
Warsa, James S. [Los Alamos National Laboratory; Prinja, Anil K. [Los Alamos National Laboratory
2012-06-14
The Fokker-Planck equation: (1) Describes the transport and interactions of charged particles, (2) Many small-angle scattering collisions, (3) Asymptotic limit of the Boltzmann equation (Pomraning, 1992), and (4) The Boltzmann collision operator becomes the angular Laplacian. SN angular discretization: (1) Angular flux is collocated at the SN quadrature points, (2) The second-order derivatives in the Laplacian term must be discretized, and (3) Weighted finite-difference method preserves zeroth and first moments (Morel, 1985). Moment-preserving methods: (1) Collocate the Fokker-Planck operator at the SN quadrature points, (2) Develop several related and/or equivalent methods, and (3) Motivated by discretizations for the angular derivative appearing in the transport equation in one-dimensional spherical coordinates.
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 (?ex = 270 nm), which is useful to recognize alcohols. All products were characterized by thermal analyses, and in particular, calcination of [Ag(L3)2](PF6)?CH3OH at 600 °C finally produces silver(0) microcrystalline morphology.
Liu, Kai; Zheng, Yuhua; Yang, Mei; Jia, Guang; Guo, Ning; Song, Yanhua; You, Hongpeng
2011-03-01
Hierarchically spherical architectures self-assembled by nanorods of coordination polymer La(1,3,5-BTC)(H2O)6:Dy3+ have been successfully prepared on a large scale via rapid static growth in solution phase at room temperature. Interestingly, these uniform and well-dispersed 3D microspheres are sensitive to ultrasound, which can be completely transformed into 1D nanorods through simple ultrasonic treatment. The photoluminescence properties of the nano/microstructured La(1,3,5-BTC)(H2O)6:Dy3+ are also investigated in detail, indicating that the obtained lanthanum 1,3,5-benzenetricarboxylate is a new promising host material for the luminescence of Dy3+ ions. PMID:21449331
Lin, Ping; Clegg, William; Harrington, Ross W; Henderson, Richard A; Fletcher, Ashleigh J; Bell, Jon; Thomas, K Mark
2006-05-15
Addition of [Mo(V)2O2S2(edt)2]2- (edt =1,2-ethanedithiolate) to acetonitrile and/or methanol solutions of MnII containing bipyridines [4,4'-trimethylenedipyridine (TDP), 4,4'-bipyridine (4,4'-bpy), 2,2'-bipyridine (2,2'-bpy)] or 15-crown-5 produces three new heterometallic cluster coordination polymers, [Mn2[Mo2O2S2(edt)2]2(TDP)3(CH3OH)2(NCMe)2].3CH3OH.0.25MeCN (1), [Mn(TDP)2(H2O)2]2+[Mn[Mo2O2S2(edt)2)2(TDP)2
Yang, Ting-Hai; Silva, Ana Rosa; Fu, Lianshe; Shi, Fa-Nian
2015-07-21
Reactions of rare earth chlorides, N-(phosphonomethyl)iminodiacetic acid (H4pmida) and ferrous oxalate dihydrate under ionothermal conditions result in four new isostructural 3d-4f heterometal coordination polymers, [LnFe(III)Fe(Hpmida)6]·2H2O {Ln = Eu (), Dy (), Ho () and Y ()}. All compounds were characterized by infrared spectroscopy, elemental analysis, thermogravimetric analysis, and X-ray diffraction. The compounds feature a very interesting three dimensional (3-D) structure built up from a secondary building unit, [Fe2(Hpmida)2](2-) and possess a new topology type and complicated unique tilings. The catalytic properties of compounds were investigated showing that these types of compounds are heterogeneous catalysts in the Knöevenagel condensation with high selectivity. PMID:26148862
V. V. Ponomareva; K. V. Domasevich; V. V. Komarchuk; J. Sieler; H. Krautscheid; V. V. Skopenko
2006-01-01
New coordination polymers based on 3,3?,5,5?-tetramethyl-4,4?-bipyrazole (L) with the composition [M2(L)4A(NCS)2] (M2+ = Co2+, Zn2+, Cd2+; A2? = SiF\\u000a 6\\u000a 2?\\u000a , SeO\\u000a 4\\u000a 2?\\u000a ) have been synthesized and characterized by IR spectroscopy and X-ray diffraction. According to X-ray diffraction data, cobalt\\u000a compounds crystallize in the orthorhombic system with the following unit cell parameters, [Co2(L)4SiF6(NCS)2] · 3CHCl3 · CH3OH:
NASA Astrophysics Data System (ADS)
Ar?c?, Mürsel; Ye?ilel, Okan Zafer; Keskin, Seda; ?ahin, Onur
2014-02-01
Two new coordination polymers, namely, [Co(?-nip)(?-bpe)]n (1) and [Zn(?-nip)(?-bpe)]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 CO2/CH4 adsorption and separation were performed. Complex 1 consists of two dimensional (2D) (4,4) grid networks with the point symbol of 44.62. Complex 2 exhibits a 3-fold interpenetrating 3D framework with 65.8-dmp topology. Thermal properties of the complexes showed that both complexes were stable over 320 °C. Simulation studies demonstrated that complex 2 can separate CO2 from CH4 at low pressures at 273 K.
He, Jun; Cao, Peng; Wu, Chao; Huang, Jiahong; Huang, Jian; He, Yonghe; Yu, Lin; Zeller, Matthias; Hunter, Allen D; Xu, Zhengtao
2015-07-01
From a hydrothermal reaction using CuI, KI, and 3,3'5,5'-tetramethyl-4,4'-bipyrazole (TMBP), the triiodide anion I3(-) has been integrated into the water-stable 2D coordination polymer Cu(TMBP)I3 (1). In contrast with other metal triiodide complexes, 1 features remarkably small distortions in the bond distances associated with the I3(-) units (i.e., the Cu-I and I-I bonds), which effectively link up the copper(I) centers into infinite CuI3 chains. The electronic band gaps and electrical conductivity data are also found to be consistent with the I3(-) ion acting as an effective linker across the copper(I) centers. PMID:26098817
Negative Refraction Angular Characterization in One-Dimensional Photonic Crystals
Lugo, Jesus Eduardo; Doti, Rafael; Faubert, Jocelyn
2011-01-01
Background Photonic crystals are artificial structures that have periodic dielectric components with different refractive indices. Under certain conditions, they abnormally refract the light, a phenomenon called negative refraction. Here we experimentally characterize negative refraction in a one dimensional photonic crystal structure; near the low frequency edge of the fourth photonic bandgap. We compare the experimental results with current theory and a theory based on the group velocity developed here. We also analytically derived the negative refraction correctness condition that gives the angular region where negative refraction occurs. Methodology/Principal Findings By using standard photonic techniques we experimentally determined the relationship between incidence and negative refraction angles and found the negative refraction range by applying the correctness condition. In order to compare both theories with experimental results an output refraction correction was utilized. The correction uses Snell's law and an effective refractive index based on two effective dielectric constants. We found good agreement between experiment and both theories in the negative refraction zone. Conclusions/Significance Since both theories and the experimental observations agreed well in the negative refraction region, we can use both negative refraction theories plus the output correction to predict negative refraction angles. This can be very useful from a practical point of view for space filtering applications such as a photonic demultiplexer or for sensing applications. PMID:21494332
Traveling waves in a one-dimensional model of hemodynamics
NASA Astrophysics Data System (ADS)
Barlukova, A. M.; Cherevko, A. A.; Chupakhin, A. P.
2014-11-01
We consider a one-dimensional model of hemodynamics—blood flow in the blood vessels—which is based on the Navier-Stokes equations averaged over the cross section of the vessel, and conjugate with a linear or nonlinear model for the elastic wall of the vessel. The objective is to study traveling wave solutions using this model. For such solutions, the system of partial differential equations reduces to an ordinary differential equation of the fourth order. The only singular point of the corresponding system of differential equations is found. It is established that at the singular point, the linearization matrix of the system has real or complex roots for different values of the parameters of the problem. With a special choice of the parameters, it has four complex conjugate roots with a nonzero real part or purely imaginary roots. For this case, the effect of the model parameter corresponding to the viscoelastic response of the vessel wall on the solution is investigated. Numerical experiments are performed to verify and analyze the results, and various modes of blood movement are discussed.
Inelastic collapse in one-dimensional driven systems under gravity.
Wakou, Jun'ichi; Kitagishi, Hiroyuki; Sakaue, Takahiro; Nakanishi, Hiizu
2013-04-01
We study inelastic collapse in a one-dimensional N-particle system when the system is driven from below under gravity. We investigate the hard-sphere limit of inelastic soft-sphere systems by numerical simulations to find how the collision rate per particle n(coll) increases as a function of the elastic constant of the sphere k when the restitution coefficient e is kept constant. For systems with large enough N>/~20, we find three regimes in e depending on the behavior of n(coll) in the hard-sphere limit: (i) an uncollapsing regime for 1?e>e(c1), where n(coll) converges to a finite value, (ii) a logarithmically collapsing regime for e(c1)>e>e(c2), where n(coll) diverges as n(coll)~logk, and (iii) a power-law collapsing regime for e(c2)>e>0, where n(coll) diverges as n(coll)~k(?) with an exponent ? that depends on N. The power-law collapsing regime shrinks as N decreases and seems not to exist for the system with N=3, while, for large N, the size of the uncollapsing and the logarithmically collapsing regime decreases as e(c1)=/~1-2.6/N and e(c2)=/~1-3.0/N. We demonstrate that this difference between large and small systems exists already in the inelastic collapse without external drive and gravity. PMID:23679401
Index theory of one dimensional quantum walks and cellular automata
D. Gross; V. Nesme; H. Vogts; R. F. Werner
2011-08-26
If a one-dimensional quantum lattice system is subject to one step of a reversible discrete-time dynamics, it is intuitive that as much "quantum information" as moves into any given block of cells from the left, has to exit that block to the right. For two types of such systems - namely quantum walks and cellular automata - we make this intuition precise by defining an index, a quantity that measures the "net flow of quantum information" through the system. The index supplies a complete characterization of two properties of the discrete dynamics. First, two systems S_1, S_2 can be pieced together, in the sense that there is a system S which locally acts like S_1 in one region and like S_2 in some other region, if and only if S_1 and S_2 have the same index. Second, the index labels connected components of such systems: equality of the index is necessary and sufficient for the existence of a continuous deformation of S_1 into S_2. In the case of quantum walks, the index is integer-valued, whereas for cellular automata, it takes values in the group of positive rationals. In both cases, the map S -> ind S is a group homomorphism if composition of the discrete dynamics is taken as the group law of the quantum systems. Systems with trivial index are precisely those which can be realized by partitioned unitaries, and the prototypes of systems with non-trivial index are shifts.
Fractal spectra in generalized Fibonacci one-dimensional magnonic quasicrystals
NASA Astrophysics Data System (ADS)
Costa, C. H. O.; Vasconcelos, M. S.; Barbosa, P. H. R.; Barbosa Filho, F. F.
2012-07-01
In this work we carry out a theoretical analysis of the spectra of magnons in quasiperiodic magnonic crystals arranged in accordance with generalized Fibonacci sequences in the exchange regime, by using a model based on a transfer-matrix method together random-phase approximation (RPA). The generalized Fibonacci sequences are characterized by an irrational parameter ?(p,q), which rules the physical properties of the system. We discussed the magnonic fractal spectra for first three generalizations, i.e., silver, bronze and nickel mean. By varying the generation number, we have found that the fragmentation process of allowed bands makes possible the emergence of new allowed magnonic bulk bands in spectra regions that were magnonic band gaps before, such as which occurs in doped semiconductor devices. This interesting property arises in one-dimensional magnonic quasicrystals fabricated in accordance to quasiperiodic sequences, without the need to introduce some deferent atomic layer or defect in the system. We also make a qualitative and quantitative investigations on these magnonic spectra by analyzing the distribution and magnitude of allowed bulk bands in function of the generalized Fibonacci number Fn and as well as how they scale as a function of the number of generations of the sequences, respectively.
Transition to coarsening for confined one-dimensional membranes
Thomas Le Goff; Paolo Politi; Olivier Pierre-Louis
2015-04-28
We discuss the dynamics of membranes confined between two attractive walls with arbitrary permeabilities. We use a two-dimension model, so that the membrane is effectively a one-dimensional object. In a previous work, we have shown that this model predicts frozen states caused by bending rigidity-induced oscillatory interactions between kinks (or domain walls). We here demonstrate that in the presence of membrane tension, potential asymmetry, or thermal noise, there is a finite threshold above which frozen states disappear, and perpetual coarsening is restored. Depending on the driving force, the transition to coarsening exhibits different scenarios. First, for membranes under tension, small tensions can only lead to transient coarsening or partial disordering, while above a finite threshold, membrane oscillations disappear and perpetual coarsening is found. Second, potential asymmetry is relevant in the non-conserved case only, i.e. for permeable walls, where it induces a drift force on the kinks, leading to a fast coarsening process via kink-antikink annihilation. However, below some threshold, the drift force can be balanced by the oscillatory interactions between kinks, and frozen adhesion patches can still be observed. Finally, noise always induces coarsening with standard exponents related to mass conservation, but the typical time for the appearance of coarsening exhibits an Arrhenius form. As a consequence, a finite noise amplitude is needed in order to observe coarsening in observable time.
One-dimensional space-time kinetics capability
Nigg, D.W.; Terry, W.K.; Weaver, W.L. (Idaho National Engineering Lab., Idaho Falls (United States))
1992-01-01
The RELAP-5 thermal-hydraulic code for modeling nuclear systems has historically offered only a point-reactor kinetics model for the simulation of reactor neutronic behavior during transients. This model is inadequate in many cases of practical interest, especially in applications involving large, loosely coupled reactor cores. The dominance ratio of these systems is in the range where the excitation of spatial harmonics can lead to significant space-time kinetics effects in some instances. Ideally, a full three-dimensional kinetics treatment would be employed in such cases. However, it is possible in some applications to obtain a sufficiently realistic representation of the time-dependent neutronic behavior of the system by explicitly considering axial space-time effects only, with a time-invariant neutron flux distribution assumed in the transverse plane. A one-dimensional space-time nodal neutron kinetics model of this type has been incorporated into the RELAP-5 code and is the subject of this paper. The discussion begins with a description of the mathematical model, which includes a previously unpublished method for accurately integrating the nodal kinetics equations over relatively large time intervals. Following this, some computed results for the kinetics model operating independently are presented and compared with a corresponding analytical benchmark solution.
Analytic Bjorken flow in one-dimensional relativistic magnetohydrodynamics
Victor Roy; Shi Pu; Luciano Rezzolla; Dirk Rischke
2015-06-22
In the initial stage of relativistic heavy-ion collisions, strong magnetic fields appear due to the large velocity of the colliding charges. The evolution of these fields appears as a novel and intriguing feature in the fluid-dynamical description of heavy-ion collisions. In this work, we study analytically the one-dimensional, longitudinally boost-invariant motion of an ideal fluid in the presence of a transverse magnetic field. Interestingly, we find that, in the limit of ideal magnetohydrodynamics, i.e., for infinite conductivity, and irrespective of the strength of the initial magnetization, the decay of the fluid energy density $e$ with proper time $\\tau$ is the same as for the time-honored "Bjorken flow" without magnetic field. Furthermore, when the magnetic field is assumed to decay $\\sim \\tau^{-a}$, where $a$ is an arbitrary number, two classes of analytic solutions can be found depending on whether $a$ is larger or smaller than one. In summary, the analytic solutions presented here highlight that the Bjorken flow is far more general than formerly thought. These solutions can serve both to gain insight on the dynamics of heavy-ion collisions in the presence of strong magnetic fields and as testbeds for numerical codes.
Using the NASA GRC Sectored-One-Dimensional Combustor Simulation
NASA Technical Reports Server (NTRS)
Paxson, Daniel E.; Mehta, Vishal R.
2014-01-01
The document is a user manual for the NASA GRC Sectored-One-Dimensional (S-1-D) Combustor Simulation. It consists of three sections. The first is a very brief outline of the mathematical and numerical background of the code along with a description of the non-dimensional variables on which it operates. The second section describes how to run the code and includes an explanation of the input file. The input file contains the parameters necessary to establish an operating point as well as the associated boundary conditions (i.e. how it is fed and terminated) of a geometrically configured combustor. It also describes the code output. The third section describes the configuration process and utilizes a specific example combustor to do so. Configuration consists of geometrically describing the combustor (section lengths, axial locations, and cross sectional areas) and locating the fuel injection point and flame region. Configuration requires modifying the source code and recompiling. As such, an executable utility is included with the code which will guide the requisite modifications and insure that they are done correctly.
Highly polarized Fermi gases: One-dimensional case
NASA Astrophysics Data System (ADS)
Giraud, S.; Combescot, R.
2009-04-01
We consider the problem of a single particle interacting with N identical fermions, at zero temperature and in one dimension. We calculate the binding energy as well as the effective mass of the single particle. We use an approximate method developed in the three-dimensional case, where the Hilbert space for the excited states of the N fermions is restricted to have at most two particle-hole pairs. When the mass of the single particle is equal to the fermion mass, we find excellent agreement with the exact results of McGuire. When the mass of the single particle is infinite, we solve exactly the problem and find again excellent agreement between approximate results and exact ones. This overall agreement in one dimension gives a strong validation for the approximate method applied in three dimensions. Moreover it shows that our approximate treatment is excellent for the one-dimensional problem in the general case with respect to the mass of the single particle.
Phonons in a one-dimensional microfluidic crystal
Beatus, Tsevi; Bar-Ziv, Roy; 10.1038/nphys432
2010-01-01
The development of a general theoretical framework for describing the behaviour of a crystal driven far from equilibrium has proved difficult1. Microfluidic crystals, formed by the introduction of droplets of immiscible fluid into a liquid-filled channel, provide a convenient means to explore and develop models to describe non-equilibrium dynamics2, 3, 4, 5, 6, 7, 8, 9, 10, 11. Owing to the fact that these systems operate at low Reynolds number (Re), in which viscous dissipation of energy dominates inertial effects, vibrations are expected to be over-damped and contribute little to their dynamics12, 13, 14. Against such expectations, we report the emergence of collective normal vibrational modes (equivalent to acoustic 'phonons') in a one-dimensional microfluidic crystal of water-in-oil droplets at Reapprox10-4. These phonons propagate at an ultra-low sound velocity of approx100 mum s-1 and frequencies of a few hertz, exhibit unusual dispersion relations markedly different to those of harmonic crystals, and g...
Weak lasing in one-dimensional polariton superlattices.
Zhang, Long; Xie, Wei; Wang, Jian; Poddubny, Alexander; Lu, Jian; Wang, Yinglei; Gu, Jie; Liu, Wenhui; Xu, Dan; Shen, Xuechu; Rubo, Yuri G; Altshuler, Boris L; Kavokin, Alexey V; Chen, Zhanghai
2015-03-31
Bosons with finite lifetime exhibit condensation and lasing when their influx exceeds the lasing threshold determined by the dissipative losses. In general, different one-particle states decay differently, and the bosons are usually assumed to condense in the state with the longest lifetime. Interaction between the bosons partially neglected by such an assumption can smear the lasing threshold into a threshold domain--a stable lasing many-body state exists within certain intervals of the bosonic influxes. This recently described weak lasing regime is formed by the spontaneously symmetry breaking and phase-locking self-organization of bosonic modes, which results in an essentially many-body state with a stable balance between gains and losses. Here we report, to our knowledge, the first observation of the weak lasing phase in a one-dimensional condensate of exciton-polaritons subject to a periodic potential. Real and reciprocal space photoluminescence images demonstrate that the spatial period of the condensate is twice as large as the period of the underlying periodic potential. These experiments are realized at room temperature in a ZnO microwire deposited on a silicon grating. The period doubling takes place at a critical pumping power, whereas at a lower power polariton emission images have the same periodicity as the grating. PMID:25787253
Tunneling through one-dimensional piecewise-constant potential barriers
NASA Astrophysics Data System (ADS)
Das, Siddhant
2015-07-01
In this paper, we examine transmission through one-dimensional potential barriers that are piecewise constant. The transfer matrix approach is adopted, and a new formula is derived for multiplying long matrix sequences that not only leads to an elegant representation of the wave function but also results in much faster computation than earlier methods. The proposed method covers a broad spectrum of potentials, of which multi-barrier systems are special cases. The procedure is illustrated with a finite lattice of nonuniform rectangular barriers—non-uniformity being a novel feature, as the uniform case has been solved exactly by Griffiths and Steinke. For the nonuniform multi-barrier problem, the intervening wells strongly influence the transmission probability. Surprisingly, we find that the wells act "individually," i.e., their influence is a function only of their width and is independent of their exact locations in a multi-barrier system. This finding leads to an observation that we have termed the "alias effect." The exact solutions are supplemented with asymptotic formulas.
Splitting of degenerate states in one-dimensional quantum mechanics
Avik Dutt; Trisha Nath; Sayan Kar; Rajesh Parwani
2012-06-11
A classic no-go theorem in one-dimensional quantum mechanics can be evaded when the potentials are unbounded below, thus allowing for novel parity-paired degenerate energy bound states. We numerically determine the spectrum of one such potential and study the parametric variation of the transition wavelength between a bound state lying inside the valley of the potential and another, von Neumann-Wigner-like state, appearing above the potential maximum. We then construct a modified potential which is bounded below except when a parameter is tuned to vanish. We show how the spacing between certain energy levels gradually decreases as we tune the parameter to approach the value for which unboundedness arises, thus quantitatively linking the closeness of degeneracy to the steepness of the potential. Our results are generic to a large class of such potentials. Apart from their conceptual interest, such potentials might be realisable in mesoscopic systems thus allowing for the experimental study of the novel states. The numerical spectrum in this study is determined using the asymptotic iteration method which we briefly review.
One-dimensional quantum walk with a moving boundary
NASA Astrophysics Data System (ADS)
Kwek, Leong Chuan; Setiawan
2011-09-01
Quantum walks are interesting models with potential applications to quantum algorithms and physical processes such as photosynthesis. In this paper, we study two models of one-dimensional quantum walks, namely, quantum walks with a moving absorbing wall and quantum walks with one stationary and one moving absorbing wall. For the former, we calculate numerically the survival probability, the rate of change of average position, and the rate of change of standard deviation of the particle's position in the long time limit for different wall velocities. Moreover, we also study the asymptotic behavior and the dependence of the survival probability on the initial particle's state. While for the latter, we compute the absorption probability of the right stationary wall for different velocities and initial positions of the left wall boundary. The results for these two models are compared with those obtained for the classical model. The difference between the results obtained for the quantum and classical models can be attributed to the difference in the probability distributions.
Bulk-edge correspondence of one-dimensional quantum walks
C. Cedzich; F. A. Grünbaum; C. Stahl; L. Velázquez; A. H. Werner; R. F. Werner
2015-05-19
We outline a theory of symmetry protected topological phases of one-dimensional quantum walks. We assume spectral gaps around the symmetry-distinguished points +1 and -1, in which only discrete eigenvalues are allowed. The phase classification by integer or binary indices extends the classification known for translation invariant systems in terms of their band structure. However, our theory requires no translation invariance whatsoever, and the indices we define in this general setting are invariant under arbitrary symmetric local perturbations, even those that cannot be continuously contracted to the identity. More precisely we define two indices for every walk, characterizing the behavior far to the right and far to the left, respectively. Their sum is a lower bound on the number of eigenstates at +1 and -1. For a translation invariant system the indices add up to zero, so one of them already characterizes the phase. By joining two bulk phases with different indices we get a walk in which the right and left indices no longer cancel, so the theory predicts bound states at +1 or -1. This is a rigorous statement of bulk-edge correspondence. The results also apply to the Hamiltonian case with a single gap at zero.
Digital noise generators using one-dimensional chaotic maps
Martínez-Ñonthe, J. A; Palacios-Luengas, L.; Cruz-Irisson, M.; Vazquez Medina, R. [Instituto Politécnico Nacional, ESIME-Culhuacan, Santa Ana 1000, 04430, D.F. (Mexico); Díaz Méndez, J. A. [Instituto Nacional de Astrofísica, Óptica y Electrónica, Luis Enrique Erro 1, Tonantzintla, Puebla (Mexico)
2014-05-15
This work shows how to improve the statistical distribution of signals produced by digital noise generators designed with one-dimensional (1-D) chaotic maps. It also shows that in a digital electronic design the piecewise linear chaotic maps (PWLCM) should be considered because they do not have stability islands in its chaotic behavior region, as it occurs in the case of the logistic map, which is commonly used to build noise generators. The design and implementation problems of the digital noise generators are analyzed and a solution is proposed. This solution relates the output of PWLCM, usually defined in the real numbers' domain, with a codebook of S elements, previously defined. The proposed solution scheme produces digital noise signals with a statistical distribution close to a uniform distribution. Finally, this work shows that it is possible to have control over the statistical distribution of the noise signal by selecting the control parameter of the PWLCM and using, as a design criterion, the bifurcation diagram.
One-dimensional ballistic aggregation: Rigorous long-time estimates
NASA Astrophysics Data System (ADS)
Martin, Philippe A.; Piasecki, Jaroslaw
1994-07-01
Aggregation of mass by perfectly inelastic collisions in a one-dimensional gas of point particles is studied. The dynamics is governed by laws of mass and momentum conservation. The motion between collisions is free. An exact probabilistic description of the state of the aggregating gas is presented. For an initial configuration of equidistant particles on the line with Maxwellian velocity distribution, the following results are obtained in the long-time limit. The probability for finding empty intervals of length growing faster than t 2/3 vanishes. The mass spectrum can range from the initial mass up to mass of order t 2/3. Aggregates with masses growing faster than t 2/3 cannot occur. Our estimates are in accordance with numerical simulations predicting t -1 decay for the number density of initial masses and a slower t -2/3 decay for the density of aggregates resulting from a large number of collisions (with masses ˜ t 2/3). Our proofs rely on a link between the considered aggregation dynamics and Brownian motion in the presence of absorbing barriers.
One-dimensional SiOC/C composite nanofibers as binder-free anodes for lithium-ion batteries
NASA Astrophysics Data System (ADS)
Li, Ying; Hu, Yi; Lu, Yao; Zhang, Shu; Xu, Guanjie; Fu, Kun; Li, Shuli; Chen, Chen; Zhou, Lan; Xia, Xin; Zhang, Xiangwu
2014-05-01
One-dimensional silicon oxycarbide (SiOC)/C composite nanofibers were fabricated by electrospinning and subsequent heat treatment. Introducing carbon matrix to SiOC anode material is an efficient way to accommodate the large volume changes during cycling and also increase the amount of free carbon, which is beneficial for improving the reversible capacity. These SiOC/C composite nanofibers form free-standing conductive membranes that can be used directly as battery electrodes without adding carbon black or polymer binder. Results show that after 80 cycles, the discharge capacity of SiOC/C composite nanofiber anodes is 70% higher than that of Si/C nanofiber anodes and more than 1.5 times larger than those of commercial anodes made from graphite. It is, therefore, demonstrated that one-dimensional SiOC/C nanofibers are promising anode material with large capacities and good cycling stability.
Zohreh Rashidi Ranjbar; Ali Morsali
A new zinc(II) coordination polymer, {[Zn(bpcdp)2(DMF)4](ClO4)2·(H2O)2}n (1) bpcdp = 2,6-bis(4-pyridinecarboxamide)pyridine has been synthesized and characterized by IR, 1HNMR and 13CNMR spectroscopy. The single crystal X-ray data of compound 1 shows the zinc(II) atom has been considered as octahedral with ZnN2O4 coordination sphere. Two nitrogen atoms of bpcdp ligand and four oxygen atoms of DMF molecules have occupied coordination\\u000a sphere around zinc(II) atoms.
Zhan, Shun-Ze; Li, Mian; Zhou, Xiao-Ping; Wang, Jun-Hao; Yang, Ju-Rong; Li, Dan
2011-12-14
A supramolecular dual emissive system incorporating two classical copper(I)-cluster-based luminophores, namely, Cu(4)I(4) and Cu(3)Pz(3) (Pz = pyrazolate), is reported. The targeted luminescent coordination polymer exhibits reversible thermochromism spanning from green to orange-red. PMID:21892509
Uranyl-copper(II) heterometallic oxalate complexes: coordination polymers and frameworks.
Thuéry, Pierre; Rivière, Eric
2013-08-01
Five oxalate complexes containing both uranyl and copper(II) ions and 2,2?-bipyridine (bipy), 2,2?-bipyrimidine (bipym) or 1,10-phenanthroline (phen) as co-ligands have been synthesized under hydrothermal conditions and their crystal structures were determined. [UO2Cu(C2O4)(NO3)2(bipy)(H2O)] (1) is a molecular complex in which the two cations are connected by the bis-chelating oxalate. A one-dimensional uranyl oxalate ribbon is formed in [UO2Cu(C2O4)2(bipym)(H2O)] (2), with uranyl ions bound to two chelating anions and to a third, monodentate oxalate which holds the decorating [Cu(bipym)(H2O)]2+ groups. Complex [(UO2)2Cu2(C2O4)2(bipym)3(OH)2]·2NO3 (3) is a two-dimensional assembly in which uranyl oxalate chains are linked to one another by [Cu2(bipym)3]4+ dinuclear units through bridging hydroxide ions. Finally, [UO2Cu(C2O4)2(bipy)] (4) and [UO2Cu(C2O4)2(phen)] (5) display identical three-dimensional arrangements containing uranyl oxalate sheets connected to one another by copper oxalate dinuclear units. The magnetic properties of compounds 2 and 4 have been investigated. Weak inter-chain antiferromagnetic interactions between copper(II) atoms are present in 2, while 4 displays strong oxalate-mediated antiferromagnetic exchange (J = -335 cm(-1)). These complexes are the first uranyl-d block metal oxalate complexes to be reported. PMID:23760346
An aggregation model reduction method for one-dimensional distributed parameter systems
Skogestad, Sigurd
An aggregation model reduction method for one-dimensional distributed parameter systems Andreas of one-dimensional distributed parameter systems is presented. It inherits the concepts of the aggregated; Distributed systems; Aggre- gated modeling; Distillation Corresponding author: andreas
Göbel, Christoph; Palamarciuc, Tatiana; Lochenie, Charles; Weber, Birgit
2014-08-01
Microcrystals of the spin-crossover coordination polymer [FeL(bipy)] (L=[3,3']-[1,2-phenylenebis(iminoethylidyne)]bis-(2,4-pentanedionato)(2-), bipy=4,4'-bipyridine) have been prepared in a poly(4-vinylpyridine) (P4VP) matrix. This was done by sequential addition of the iron(II) precursor complex and the bridging ligand bipy to a P4VP matrix, and by repetition of this cycle. The obtained composite material was characterized using TEM, SEM, XRPD, and SQUID measurements, and Mössbauer spectroscopy. With repeating cycles, the size of the [FeL(bipy)] crystals in the P4VP matrix increases from submicrometer to micrometer dimensions. A strong dependence on the number of cycles is observed. Above a critical size and concentration, the microcrystals show the same cooperative spin transition as the bulk material. No indication for a gradual spin transition is observed, but the remaining iron centers are either high-spin or low-spin depending on the coordination environment. PMID:24938532
White-emissive tandem-type hybrid organic/polymer diodes with (0.33, 0.33) chromaticity coordinates.
Guo, Tzung-Fang; Wen, Ten-Chin; Huang, Yi-Shun; Lin, Ming-Wei; Tsou, Chuan-Cheng; Chung, Chia-Tin
2009-11-01
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. PMID:19997359
N. V. Maksimchuk; M. N. Timofeeva; M. S. Melgunov; A. N. Shmakov; Yu. A. Chesalov; D. N. Dybtsev; V. P. Fedin; O. A. Kholdeeva
2008-01-01
Titanium- and cobalt-monosubstituted Keggin heteropolyanions, [PW11CoO39]5? and [PW11TiO40]5?, were electrostatically bound to the chromium terephthalate polymer matrix MIL-101. The MIL-supported polyoxometalate (POM) catalysts were characterized by elemental analysis, XRD, N2 adsorption, and FT-IR-spectroscopy. The catalytic performance of both MIL-101 and the novel composite materials M-POM\\/MIL-101 was assessed in the oxidation of three representative alkenes—?-pinene, caryophyllene, and cyclohexene—using molecular oxygen and
Lama, Prem; Sañudo, E Carolina; Bharadwaj, Parimal K
2012-03-14
Two new coordination polymers have been synthesized with Mn(2+) and Dy(3+) ions using a new bent ether-bridged tricarboxylic acid ligand, o-cpiaH(3) (5-(2-carboxy-phenoxy)-isophthalic acid). The ligand readily reacts with a Mn(2+) salt in presence of pyridine (py) under hydrothermal condition to afford a 3D coordination polymer {[Mn(9)(o-cpia)(6)(py)(3)(3H(2)O)]·H(2)O}(n) (1), that contains two types of polymeric chains. One of them is merely carboxylate bridged Mn(2+) where each metal ion shows both penta- and hexa-coordination. The other chain consists of carboxylate-bridging along with terminally bound pyridines providing both penta- and hexa-coordination to each metal ion. When o-cpiaH(3) is treated with Dy(NO(3))(3).xH(2)O under solvothermal condition, it gives rise to an unusual double layer (6,6) connected 2D coordination polymer {[Dy(o-cpia)]}(n)(2), where each metal ion is hexacoordinated. The double layer 2D sheets are stacked to each other in AA··· fashion through strong C-H···? interactions to generate an overall 3D supramolecular architecture. Both the complexes have been characterized by single crystal X-ray diffraction, IR spectroscopy, thermogravimetry and elemental analysis. Variable temperature magnetic susceptibility measurements indicate that 1 exhibits metamagnetic behavior while 2 shows weak antiferromagnetic behavior. PMID:22274709
One dimensional blood flow in a planetocentric orbit
NASA Astrophysics Data System (ADS)
Haranas, Ioannis; Gkigkitzis, Ioannis
2012-05-01
All life on earth is accustomed to the presence of gravity. When gravity is altered, biological processes can go awry. It is of great importance to ensure safety during a spaceflight. Long term exposure to microgravity can trigger detrimental physiological responses in the human body. Fluid redistribution coupled with fluid loss is one of the effects. In particular, in microgravity blood volume is shifted towards the thorax and head. Sympathetic nervous system-induced vasoconstriction is needed to maintain arterial pressure, while venoconstriction limits venous pooling of blood prevents further reductions in venous return of blood to the heart. In this paper, we modify an existing one dimensional blood flow model with the inclusion of the hydrostatic pressure gradient that further depends on the gravitational field modified by the oblateness and rotation of the Earth. We find that the velocity of the blood flow VB is inversely proportional to the blood specific volume d, also proportional to the oblateness harmonic coefficient J2, the angular velocity of the Earth ?E, and finally proportional to an arbitrary constant c. For c = -0.39073 and ?H = -0.5 mmHg, all orbits result to less blood flow velocities than that calculated on the surface of the Earth. From all considered orbits, elliptical polar orbit of eccentricity e = 0.2 exhibit the largest flow velocity VB = 1.031 m/s, followed by the orbits of inclination i = 45°and 0°. The Earth's oblateness and its rotation contribute a 0.7% difference to the blood flow velocity.
Few particles correlation in a one-dimensional quasiperiodic lattice
NASA Astrophysics Data System (ADS)
Suárez, J. R.; Vallejo, E.; Carvajal, E.; Navarro, O.
2005-07-01
During the last two decades, two of the most important discoveries in condensed matter physics have been the discovery of quasicrystals and the discovery of high-Tc ceramic superconductors. These topics have generated a large number of experimental and theoretical studies in the physics of low dimension. They have also modified some of the concepts in solid state physics. For instance, it was believed that the five-fold symmetry was incompatible with a long-range order and it was not expected that ceramic materials with a high-Tc and a short coherence length exhibit superconductivity. Therefore, it is important to revise both the spatial symmetry and the electronic correlation to identify how they affect the physical properties of materials. The study of these subjects is complex since we cannot use the reciprocal space to study quasicrystals and the electronic correlation in many-body systems has not entirely been solved. Even in one-dimensional quasiperiodic structures, the interactions between electrons have often been neglected and only few results have been obtained. In this work, we solved the cases of two and three interacting particles in a Fibonacci lattice using a real-space method, the Green function technique, the renormalized perturbation expansion method and the Hubbard model. For the case of two interacting particles an analytical solution for the pairing phase diagram was obtained using the extended Hubbard Hamiltonian. For the case of three interacting particles the binding energy was numerically calculated. The results present here are compared with those obtained for the periodic and binary lattices.
One-dimensional itinerant interacting non-Abelian anyons
NASA Astrophysics Data System (ADS)
Poilblanc, Didier; Feiguin, Adrian; Troyer, Matthias; Ardonne, Eddy; Bonderson, Parsa
2013-02-01
We construct models of interacting itinerant non-Abelian anyons moving along one-dimensional chains. We focus on itinerant Ising (Majorana) and Fibonacci anyons, which are, respectively, related to SU(2)2 and SU(2)3 anyons and also, respectively, describe quasiparticles of the Moore-Read and Z3-Read-Rezayi fractional quantum Hall states. Following the derivation of the electronic large-U effective Hubbard model, we derive effective anyonic t-J models for the low-energy sectors. Solving these models by exact diagonalization, we find a fractionalization of the anyons into charge and (neutral) anyonic degrees of freedom—a generalization of spin-charge separation of electrons which occurs in Luttinger liquids. A detailed description of the excitation spectrum can be performed by combining spectra for charge and anyonic sectors. The anyonic sector is that of a squeezed chain of localized interacting anyons and, hence, is described by the same conformal field theory (CFT), with central charge c=1/2 for Ising anyons and c=7/10 or c=4/5 for Fibonacci anyons with antiferromagnetic or ferromagnetic coupling, respectively. The charge sector is the spectrum of a chain of hard-core bosons subject to phase shifts which coincide with the momenta of the combined anyonic eigenstates, revealing a subtle coupling between charge and anyonic excitations at the microscopic level (which we also find to be present in Luttinger liquids), despite the macroscopic fractionalization. The combined central charge extracted from the entanglement entropy between segments of the chain is shown to be 1+c, where c is the central charge of the underlying CFT of the localized anyon (squeezed) chain.
The one-dimensional Ly? forest power spectrum from BOSS
NASA Astrophysics Data System (ADS)
Palanque-Delabrouille, Nathalie; Yèche, Christophe; Borde, Arnaud; Le Goff, Jean-Marc; Rossi, Graziano; Viel, Matteo; Aubourg, Éric; Bailey, Stephen; Bautista, Julian; Blomqvist, Michael; Bolton, Adam; Bolton, James S.; Busca, Nicolás G.; Carithers, Bill; Croft, Rupert A. C.; Dawson, Kyle S.; Delubac, Timothée; Font-Ribera, Andreu; Ho, Shirley; Kirkby, David; Lee, Khee-Gan; Margala, Daniel; Miralda-Escudé, Jordi; Muna, Demitri; Myers, Adam D.; Noterdaeme, Pasquier; Pâris, Isabelle; Petitjean, Patrick; Pieri, Matthew M.; Rich, James; Rollinde, Emmanuel; Ross, Nicholas P.; Schlegel, David J.; Schneider, Donald P.; Slosar, Anže; Weinberg, David H.
2013-11-01
We have developed two independent methods for measuring the one-dimensional power spectrum of the transmitted flux in the Lyman-? forest. The first method is based on a Fourier transform and the second on a maximum-likelihood estimator. The two methods are independent and have different systematic uncertainties. Determination of the noise level in the data spectra was subject to a new treatment, because of its significant impact on the derived power spectrum. We applied the two methods to 13 821 quasar spectra from SDSS-III/BOSS DR9 selected from a larger sample of over 60 000 spectra on the basis of their high quality, high signal-to-noise ratio (S/N), and good spectral resolution. The power spectra measured using either approach are in good agreement over all twelve redshift bins from ?z? = 2.2 to ?z? = 4.4, and scales from 0.001 km s-1 to 0.02 km s-1. We determined the methodological andinstrumental systematic uncertainties of our measurements. We provide a preliminary cosmological interpretation of our measurements using available hydrodynamical simulations. The improvement in precision over previously published results from SDSS is a factor 2-3 for constraints on relevant cosmological parameters. For a ?CDM model and using a constraint on H0 that encompasses measurements based on the local distance ladder and on CMB anisotropies, we infer ?8 = 0.83 ± 0.03 and ns = 0.97 ± 0.02 based on H i absorption in the range 2.1 < z < 3.7. The measured values of the power spectrum and correlation matrices for all scales and all redshifts (full Tables 4 and 5) are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/559/A85
Optical parametric amplification in one-dimensional photonic bandgap structures.
Wicharn, Surawut; Buranasiri, Prathan; Ruttanapun, Chesta; Jindajitawat, Phumin
2013-09-01
In this paper, optical parametric amplification based on the degenerate four-wave mixing principle in a one-dimensional photonic bandgap (PBG) structure has been numerically studied. First, the multiple scale method was introduced to derive a complete set of nonlinear coupled-mode equations for a finite structure with different inhomogeneous nonlinear coefficients than those used in previous works. This finite structure is composed of 680 dielectric layers, which are alternating half-wave/eight-wave films. The wavelengths of the pump, signal, and idler pulses have been determined from the transmission spectrum, which was illustrated by using the transfer matrix method. The parametric interaction of the pump, signal, and idler pulses inside PBG structure has been numerically simulated by using the split-step Fourier transform method. The results of the simulation have shown that the intensities of the signal and idler have exponential growth with respect to the number of layers in the medium. Meanwhile, pump wavevector detuning directly affects the intensities of both pulses due to a band-edge phase-matching condition that might be achieved from only one optimal detuning parameter. Moreover, both the amplification gain and the conversion efficiency of the idler pulse have been shown to be dependent on the bandwidth of the pump pulse spectrum. A very narrow pulse, with a bandwidth much less than the relevant transmission peak, enables the highest amplification and conversion efficiency in this medium because the most efficient phase-matched condition occurs in this situation. Finally, the conversion efficiency grows exponentially with input pump intensity for several input signal intensities. Furthermore, the maximum conversion efficiencies directly vary with input signal intensity. PMID:24085064
Two dimensionality in quasi-one-dimensional cobalt oxides
NASA Astrophysics Data System (ADS)
Sugiyama, J.; Nozaki, H.; Brewer, J. H.; Ansaldo, E. J.; Morris, G. D.; Takami, T.; Ikuta, H.; Mizutani, U.
2006-03-01
Magnetism of quasi-one-dimensional (1D) cobalt oxides ACoO ( A=Ca, Sr and Ba, n=1-5 and ?) was investigated by ?+SR using polycrystalline samples, at temperatures from 300 K down to 1.8 K. The wTF- ?+SR experiments showed the existence of a magnetic transition in all six samples investigated. The onset temperature of the transition (Tcon) was found to decrease with n; that is, 100±25, 90±10, 85±10, 65±10 50±10, and 15±1 K for n=1-5, and ?, respectively. In particular, for the samples with n=2-5, Tcon was detected only by the present ?+SR measurements. A muon spin oscillation was clearly observed in both Ca 3Co 2O 6(n=1) and BaCoO 3(n=?), whereas only a fast relaxation is apparent even at 1.8 K in the other four samples ( n=2-5). Taking together with the fact that the paramagnetic Curie temperature ranges from -150 to -200 K for the compound with n=2 and 3, the ?+SR result indicates that a two-dimensional (2D) short-range antiferromagnetic (AF) order, which has been thought to be unlikely to exist at high T due to a relatively strong 1D F interaction, appears below Tcon for all compounds with n=1-5; but quasi-static long-range AF order formed only in Ca 3Co 2O 6, below 25 K. For BaCoO 3(n=?), as T decreased from 300 K, 1D F order appeared below 53 K, and a sharp 2D AF transition occurred at 15 K.
Designing software for one-dimensional partial differential equations
N. L. Schryer
1990-01-01
Users of software for solving partial differential equations are often surprised by its inability to formulate their problems.Computer scientists speak of partial differential equations (PDEs) as canonical coupled systems, typically in divergence form. Physicists, chemists, and engineers start with the same description, but then add real-world things like “Rankine-Hugoniot” conditions, integro-differential operators, and Eulerian (moving) coordinate systems.This paper describes a
Conditions on the Use of the One-dimensional Heat Equation
Pincock, Chris
Conditions on the Use of the One-dimensional Heat Equation Christopher Pincock Abstract. This paper explores the conditions under which scientists are warranted in adding the one-dimensional heat equation a modicum of advanced mathematics: the one-dimensional heat equation. For u(x, t) represent- ing
Song, Juan [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710069 (China); Wang, Ji-Jiang [School of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Chemical Reaction Engineering, Yanan University, Yan'an 716000 (China); Hu, Huai-Ming, E-mail: ChemHu1@NWU.EDU.CN [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710069 (China); Wu, Qing-Ran; Xie, Juan; Dong, Fa-Xin; Yang, Meng-Lin; Xue, Gang-Lin [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710069 (China)
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 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. - 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.
D. I. Nagirner; S. L. Kirusheva
2008-08-25
In order to choose a numerical method for solving the time dependent equations of radiative transport, we obtain an exact solution for the time dependent radiation field in a one dimensional infinite medium with monochromatic, isotropic scattering for sources with an arbitrary spatial distribution and an arbitrary time variation of their power. The Lax-Wendroff method seems to be the most suitable. Because it is assumed that radiation delay is caused by the finite speed of light, the following difficulty arises when the numerical method is used: the region of variation of the variables (dimensionless coordinate \\tau and time t) is triangular (the inequality \\tautime and coordinate. By comparing the numerical and exact solutions for a point source with a given time dependence for its power and with pure scattering, the steps in the variables required to obtain a desired accuracy are estimated. This numerical method can be used to calculate the intensity and polarization of the radiation from sources in the early universe during epochs close to the recombination epoch.
Effective one-dimensional diffusion on curved surfaces: Catenoid and pseudosphere
NASA Astrophysics Data System (ADS)
Chacón-Acosta, Guillermo; Pineda, Inti; Dagdug, Leonardo
2014-01-01
We present the effective diffusion coefficient for the diffusion in a narrow generally asymmetric channel embedded on a curved surface, in the case of simple diffusion of pointlike particles without interaction and under no external forces. First, we define the diffusion equation for anisotropic diffusion involving a version of the Laplace-Beltrami operator. Then, we choose symmetric surfaces whose metric components only depend on one of the local coordinates and thus, apply the Kalinay-Percus' projection method. With this method one can project two-dimensional anisotropic diffusion into the corresponding effective one-dimensional generalized Fick-Jacobs equation to the lowest order. The perturbation series to all orders converges and as a general result the effective diffusion coefficient on a curved surface depending on the longitudinal local coordinate was obtained and is presented. It contains metric terms that can be related with the Gaussian curvature of the surface. We illustrate our results by studying asymmetric conical channel configurations on two surfaces, namely, the catenoid that is a minimal surface, and the pseudosphere that is a surface with negative constant curvature.
Survival of interacting Brownian particles in crowded one-dimensional environment
NASA Astrophysics Data System (ADS)
Ryabov, Artem; Chvosta, Petr
2012-02-01
We investigate a diffusive motion of a system of interacting Brownian particles in quasi-one-dimensional micropores. In particular, we consider a semi-infinite 1D geometry with a partially absorbing boundary and the hard-core inter-particle interaction. Due to the absorbing boundary the number of particles in the pore gradually decreases. We present the exact analytical solution of the problem. Our procedure merely requires the knowledge of the corresponding single-particle problem. First, we calculate the simultaneous probability density of having still a definite number (N - k) of surviving particles at definite coordinates. Focusing on an arbitrary tagged particle, we derive the exact probability density of its coordinate. Second, we present a complete probabilistic description of the emerging escape process. The survival probabilities for the individual particles are calculated, the first and the second moments of the exit times are discussed. Generally speaking, although the original inter-particle interaction possesses a point-like character, it induces entropic repulsive forces which, e.g., push the leftmost (rightmost) particle towards (opposite) the absorbing boundary thereby accelerating (decelerating) its escape. More importantly, as compared to the reference problem for the non-interacting particles, the interaction changes the dynamical exponents which characterize the long-time asymptotic dynamics. Interesting new insights emerge after we interpret our model in terms of (a) diffusion of a single particle in a N-dimensional space, and (b) order statistics defined on a system of N-independent, identically distributed random variables.
Tiana, Davide; Hendon, Christopher H; Walsh, Aron; Vaid, Thomas P
2014-07-28
The combination of organic and inorganic chemical building blocks to form metal-organic frameworks (MOFs) offers opportunities for producing functional materials suitable for energy generation, storage and conversion. However, such applications rely on robust electron transport and the design of conductive hybrid materials is still in its infancy. Here we apply density functional theory to assess the important structural and compositional factors for forming conducting MOFs. We focus on 1D metal-organic polymers as a model system and assess the choice of organic, inorganic and linking units. The results demonstrate that electronic communication is sensitive to the energy and symmetry of the frontier orbitals associated with the organic and inorganic building blocks and offers guidance on how to optimise electrical conduction in hybrid materials. PMID:24569694
Quasi-one-dimensional models for glassy dynamics
NASA Astrophysics Data System (ADS)
Pal, Prasanta
2011-12-01
We describe analytical calculations and simulations of the quasi-one-dimensional (Q1-D) model for glassy dynamics. In the Q1-D models, hard rods undergo single-file diffusion through a series of narrow channels connected by J intersections. The topology of the model is specified by J, the maximum number of rods in each middle channel K, and the number of rods N. We assume that the rods cannot turn at the intersections, and thus there is a single, continuous route through the system. This model displays hallmarks of glassy dynamics including caging behavior and subdiffusion, rapid growth in the structural relaxation time and collective particle rearrangements. The mean-square displacement Sigma(t) for the Q1-D model displays four dynamical regimes: 1) short-time diffusion Sigma( t) ˜ t, 2) a plateau Sigma(t) ˜ t0 caused by caging behavior, 3) single-file diffusion characterized by anomalous scaling Sigma(t) ˜ t0.5 at intermediate times, and 4) a crossover to long-tine diffusion Sigma(t) ˜ t for times that grow with the system size. We develop a general procedure for calculating analytically the structural relaxation time tD, beyond which the system undergoes long-time diffusion, as a function of density and system topology. The method involves several steps: 1) uniquely defining the set of microstates for the system and transitions among them, 2) constructing networks of connected microstates and identifying minimal, closed, directed loops that give rise to structural relaxation, 3) calculating the probabilities for obtaining each of the microstates that form the closed loops and for transitioning from one microstate to another, and 4) using these probabilities to deduce the dependence of tD on packing fraction. We find that to obeys power-law scaling tD ˜ (? g-?)-alpha, where ? g (the packing fraction corresponding to complete kinetic arrest) and alpha depend on the system topology, and can be calculated exactly. The analytical calculations are supported quantitatively by Monte Carlo simulations.
Chen, Hui-Ru; Zhang, Wen-Wen
2014-11-01
The title Cd(II) coordination framework, [Cd(C15H8O5)(H2O)]n or [Cd(bpdc)(H2O)]n [H2bpdc is 2-(4-carboxybenzoyl)benzoic acid], has been prepared and characterized using IR spectroscopy, elemental analysis, thermal analysis and single-crystal X-ray diffraction. Each Cd(II) centre is six-coordinated by two O atoms from one 2-(4-carboxylatobenzoyl)benzoate (bpdc(2-)) ligand in chelating mode, three O-donor atoms from three other bpdc(2-) anions and one O atom from a coordinated water molecule in an octahedral coordination environment. Two crystallographically equivalent Cd(II) cations are bridged by one O atom of the 2-carboxylate group of one bpdc(2-) ligand and by both O atoms of the 4-carboxylate group of a second bpdc(2-) ligand to form a binuclear [(Cd)2(O)(OCO)] secondary building unit. Adjacent secondary building units are interlinked to form a one-dimensional [Cd(OCO)2]n chain. The bpdc(2-) ligands link these rod-shaped chains to give rise to a complex two-dimensional [Cd(bpdc)]n framework with a 4,4-connected binodal net topology of point symbol {4(3).6(2).8}. The compound exhibits a strong fluorescence emission and typical ferroelectric behaviour in the solid state at room temperature. PMID:25370111
Electrochemical synthesis of one-dimensional nanostructures for sensor and spintronic applications
NASA Astrophysics Data System (ADS)
Hangarter, Carlos Maldonado
One-dimensional (1-D) nanostructures, such as nanowires and nanotubes, are attractive building blocks for electronics because of their small sizes, which provide for extremely high density devices, and their unique properties that emerge from their diminutive sizes and increased surface to volume ratios. In addition their extremely high aspect ratios offer researchers the potential to build striped and coaxial structures with different components aligned along the cylindrical or radial axis of the wire, respectively. Composition modulation can be used to incorporate multiple functionalities from intrinsic properties of the material or through interfacial phenomena. However, spatial manipulation and the ability to assemble and position nanostructures in a controlled manner so they are registered to lithographically defined contacts is a critical step toward scalable integration in high-density nanodevices. In this dissertation a generalized template directed approach with ancillary assembly, contact, and displacement techniques were utilized to synthesize and characterize individual nanostructures from uniquely configured conducting polymer, magnetic, and semiconductor nanomaterials for sensor and spintronic applications. Conducting polymers are particularly appealing because they exhibit tunable transport characteristics along with electronic, magnetic and optical properties of metals or semiconductors while retaining the attractive mechanical properties and processing advantages of polymers. In the first part of this work single component conducting polymer nanowires were electropolymerized, dielectrophoretically assembled, and contacted via maskless electrodeposition. Maskless electrodeposition was developed to selectively electrodeposit material on prefabricated microelectrode, embedding the nanowire ends. Two different conducting polymers were investigated, polypyrrole (PPy) and polyethylendioxythiophene (PEDOT). Individual PPy nanowire devices demonstrated enhanced sensitivity to ammonia vapors, and PEDOT nanowire devices exhibited strong responses to volatile organic compounds. The gas sensing performances of these single nanowire devices were tuned by dopant type and synthesis conditions. Alternatively, single PEDOT nanowire devices were also completely coated in ferromagnetic material by implementing non-selective electrodeposition. The magnetoresistance (MR) of these devices displayed anomalous behavior, drastically deviating from typical anisotropic magnetoresistance responses. Additionally, multi-segmented noble/oxidizable nanowires were electrodeposited and subjected to galvanic displacement to create nanopeapod devices with Au peas and Te pods.
NASA Astrophysics Data System (ADS)
Zhong, Fang; Zu-li, Liu; Kai-lun, Yao; Zai-guang, Li
1995-12-01
Based on a theoretical model proposed for quasi-one-dimensional organic polymer ferromagnets, the next-nearest neighbor hopping interactions of ?-electrons are considered. Allowing for full lattice relaxation, a set of self-consistent equations is established to study the system. The spin-density-wave (SDW) and the possible ferromagnetic ground state of the system are investigated in detail. It is found that the next-nearest neighbor hopping interactions will make the SDW stronger and consequently make the ferromagnetic state more stable as compared with the nonmagnetic reference state.
Quantum Tunneling of an Acoustic Polaron in One-Dimensional Electron-Lattice System
NASA Astrophysics Data System (ADS)
Ono, Yoshiyuki; Ebinuma, Takashi; Ozawa, Toshiyuki
More than two decades ago, Donovan and Wilson [1] found peculiar charge carriers with an anomalously high mobility in photo-conduction experiments on polydiacetylene which belongs to conjugated polymers and could be regarded as a quasi-one-dimensional system; for example, in the single crystal of polydiacetylene toluene sulphonate, one of typical polydiacetylene, the minimum distance between neighboring polymer chains is 0.75 nm [2] which is much larger than the bond length between carbon atoms (˜ 0.13 nm). The characteristics of the photo-excited charge carriers are summarized as follows; (1) they have a rather high mobility which is estimated to be no less than 20 m2/(sec·V), and (2) their drift velocity shows saturation at a value of the order of the sound velocity v s of the system in the applied electric field with the strength 102 to 106 V/m. For a possible explanation of this charge carrier, Wilson [3] proposed an acoustic polaron which is a composite of an electron near the conduction band bottom and lattice distortions induced by the presence of the electron and giving rise to an effective attractive potential confining the electron to a locally distorted lattice region. In fact, starting from Su, Schrieffer and Heeger's (SSH) model [4] which is one of the standard theoretical models for one-dimensional coupled electron-lattice systems, Wilson [3] could derive theoretically the following properties of an acoustic polaron within the continuum approximation which is justified in the weak coupling limit; (1) the polaron has a saturation velocity equal to the sound velocity of the system, (2) the extent of the polaron (referred to as "width" in the following) decreases with increasing velocity and tends to vanish as the velocity v approaches the saturation velocity (= the sound velocity, ), and (3) the energy of the moving polaron diverges as (v s -v)-3 when the polaron velocity v approaches v s . These properties of the acoustic polaron were confirmed later by numerical simulations [5] treating the SSH model as it is without assuming the weak coupling limit; details of these simulations will be explained in the following section.
Quantum Tunneling of an Acoustic Polaron in One-Dimensional Electron-Lattice System
NASA Astrophysics Data System (ADS)
Ono, Yoshiyuki; Ebinuma, Takashi; Ozawa, Toshiyuki
More than two decades ago, Donovan and Wilson [1] found peculiar charge carriers with an anomalously high mobility in photo-conduction experiments on polydiacetylene which belongs to conjugated polymers and could be regarded as a quasi-one-dimensional system; for example, in the single crystal of polydiacetylene toluene sulphonate, one of typical polydiacetylene, the minimum distance between neighboring polymer chains is 0.75 nm [2] which is much larger than the bond length between carbon atoms ( 0.13 nm). The characteristics of the photo-excited charge carriers are summarized as follows; (1) they have a rather high mobility which is estimated to be no less than 20 m2/(secV), and (2) their drift velocity shows saturation at a value of the order of the sound velocity of the system in the applied electric field with the strength 102 to 106 V/m. For a possible explanation of this charge carrier, Wilson [3] proposed an acoustic polaron which is a composite of an electron near the conduction band bottom and lattice distortions induced by the presence of the electron and giving rise to an effective attractive potential confining the electron to a locally distorted lattice region. In fact, starting from Su, Schrieffer and Heeger''s (SSH) model [4] which is one of the standard theoretical models for one-dimensional coupled electron-lattice systems, Wilson [3] could derive theoretically the following properties of an acoustic polaron within the continuum approximation which is justified in the weak coupling limit; (1) the polaron has a saturation velocity equal to the sound velocity of the system, (2) the extent of the polaron (referred to as width in the following) decreases with increasing velocity and tends to vanish as the velocity v approaches the saturation velocity (= the sound velocity, ), and (3) the energy of the moving polaron diverges as when the polaron velocity v approaches . These properties of the acoustic polaron were confirmed later by numerical simulations [5] treating the SSH model as it is without assuming the weak coupling limit; details of these simulations will be explained in the following section.
NASA Astrophysics Data System (ADS)
Ceyhan, Gökhan; Köse, Muhammet; Tümer, Mehmet; Dal, Hakan
2015-05-01
A polymeric potassium complex of p-nitrophenol was synthesized and characterized by analytical and spectroscopic techniques. Molecular structure of the complex was determined by single crystal X-ray diffraction study. X-ray structural data show that crystals contain polymeric K+ complex of p-nitrophenol. Asymmetric unit consists of one p-nitrophenolate, one K+ ion and one water molecule. All bond lengths and angles in the phenyl rings have normal Csp2-Csp2 values and are in the expected ranges. The p-nitrophenolate is close to planar with small distortions by some atoms. Each potassium ion in the polymeric structure is identical and eight-coordinate, bonded to four nitro, two phenolate oxygen atoms from five p-nitrophenolate ligands and two oxygen atoms from two water molecules. Electronic, electrochemical, photoluminescence and thermal properties of the complex were also investigated.
NASA Astrophysics Data System (ADS)
Gu, Jin-Zhong; Wu, Jiang; Kirillov, Alexander M.; Lv, Dong-Yu; Tang, Yu; Wu, Jin-Cai
2014-05-01
A series of six coordination compounds {[Zn(5-Brnic)2]·1.5H2O}n (1), [Cd(5-Brnic)2]n (2), [Co(5-Brnic)2(H2O)2]n (3), [Zn(5-Brnic)2(H2biim)]n (4), {[Cd(5-Brnic)2(phen)]·H2O}n (5), and [Pb(5-Brnic)2(phen)] (6) have been generated by the hydrothermal method from the metal(II) nitrates, 5-bromonicotinic acid (5-BrnicH), and an optional ancillary 1,10-phenanthroline (phen) or 2,2?-biimidazole (H2biim) ligand. All the products 1-6 have been characterized by IR spectroscopy, elemental, thermal, powder and single-crystal X-ray diffraction analyses. Their 5-bromonicotinate-driven structures vary from the 3D metal-organic framework with the seh-3,5-P21/c topology (in 2) and the 2D interdigitated layers with the sql topology (in 1 and 3), to the 1D chains (in 4 and 5) and the 0D discrete monomers (in 6). The 5-bromonicotinate moiety acts as a versatile building block and its tethered bromine atom plays a key role in reinforcing and extending the structures into diverse 3D supramolecular networks via the various halogen bonding Br⋯O, Br⋯Br, and Br⋯? interactions, as well as the N-H⋯O and C-H⋯O hydrogen bonds. The obtained results demonstrate a useful guideline toward engineering the supramolecular architectures in the coordination network assembly under the influence of various halogen bonding interactions. The luminescent (for 1, 2, 4, 5, and 6) and magnetic (for 3) properties have also been studied and discussed in detail.
Zhang, Shaowei; Duan, Eryue; Han, Zongsu; Li, Leilei; Cheng, Peng
2015-07-01
Three lanthanide coordination polymers (Ln-CPs) formulated as [Ln(azdc)(HCOO)]n [Ln = Gd(III) (1), Tb(III) (2), Dy(III) (3); H2azdc = 4,4'-azobenzoic acid] have been successfully obtained by the solvothermal reaction of Ln(III) ions with H2azdc ligands in the mixed solvent N,N-dimethylformamide (DMF)/H2O. Compared with our previous work on Ln-CPs with H2azdc ligands, [Gd2(azdc)3(DMA)2]n·2nDMA (1'; DMA = dimethylacetamide), in which the DMA molecules coordinate to Gd(III) ions that are replaced by HCOO(-) groups in 1, resulting in the distinct structures and properties of the final products. Adjacent Ln(III) ions in 1-3 are connected by HCOO(-) groups through bridging and chelating modes to give 2D layers, which are further linked by azdc(2-) ligands to produce 3D frameworks. Magnetic results declare that antiferromagnetic couplings exist in 1, although two different magnetic interactions among adjacent Gd(III) ions derived from antiferromagnetic interactions of the smaller Gd-O-Gd angles (Gd···Gd distances) and weak ferromagnetic interactions of the larger Gd-O-Gd angles (Gd···Gd distances) coexist in 1. Furthermore, the magnetocaloric effect (MCE) value of 1 is 1.5 times as large as that of 1'. More importantly, 1 exhibits excellent stabilities toward air, thermal, solvent, and acid/alkaline conditions. The results manifest that the crystalline structure of 1 can be stable at at least 425 °C supported by the in situ variable-temperature powder X-ray diffraction patterns and thermogravimetric analyses, in air for at least 3 months, and in common solvents for more than 1 week, as well as in aqueous solutions ranging from pH = 2 to 12 for more than 1 week. PMID:26097991
Uranyl Sensitization of Samarium(III) Luminescence in a Two-Dimensional Coordination Polymer
Knope, Karah E. [George Washington Univ., Washington, DC (United States); de Lill, Daniel T. [Univ. of Nevada, Reno, NV (United States); Rowland, Clare E. [George Washington Univ., Washington, DC (United States); Cantos, Paula M. [George Washington Univ., Washington, DC (United States); de Bettencourt-Dias, Ana [Univ. of Nevada, Reno, NV (United States); Cahill, Christopher L. [George Washington Univ., Washington, DC (United States)
2012-01-02
Heterometallic carboxyphosphonates UO?^{2+}/Ln^{3+} have been prepared from the hydrothermal reaction of uranyl nitrate, lanthanide nitrate (Ln = Sm, Tb, Er, Yb), and phosphonoacetic acid (H?PPA). Compound 1, (UO?)?(PPA)(HPPA)?Sm(H?O)·2H?O (1) adopts a two-dimensional structure in which the UO?^{2+} metal ions bind exclusively to the phosphonate moiety, whereas the Ln^{3+} ions are coordinated by both phosphonate and carboxylate functionalities. Luminescence studies of 1 show very bright visible and near-IR samarium(III)-centered emission upon direct excitation of the uranyl moiety. The Sm^{3+} emissive state exhibits a double-exponential decay with lifetimes of 67.2 ± 6.5 and 9.0 ± 1.3 ?s as measured at 594 nm, after excitation at both 365 and 420 nm. No emission is observed in the region typical of the uranyl cation, indicating that all energy is either transferred to the Sm^{3+} center or lost to nonradiative processes. Herein we report the synthesis, crystal structure, and luminescent behavior of 1, as well as those of the isostructural terbium, erbium, and ytterbium analogues.
Exact solution of the one-dimensional super-symmetric t-J model with unparallel boundary fields
NASA Astrophysics Data System (ADS)
Zhang, Xin; Cao, Junpeng; Yang, Wen-Li; Shi, Kangjie; Wang, Yupeng
2014-04-01
The exact solution of the one-dimensional super-symmetric t-J model under generic integrable boundary conditions is obtained via the Bethe ansatz methods. With the coordinate Bethe ansatz, the corresponding R-matrix and K-matrices are derived for the second eigenvalue problem associated with spin degrees of freedom. It is found that the second eigenvalue problem can be transformed into that of the transfer matrix of the inhomogeneous XXX spin chain, which allows us to obtain the spectrum of the Hamiltonian and the associated Bethe ansatz equations by the off-diagonal Bethe ansatz method.
Zhang, Yingwei; Luo, Yonglan; Tian, Jingqi; Asiri, Abdullah M.; Al-Youbi, Abdulrahman O.; Sun, Xuping
2012-01-01
In this paper, we report on the large-scale, rapid synthesis of uniform rectangular coordination polymer nanoplates (RCPNs) assembled from Cu(II) and 4,4?-bipyridine for the first time. We further demonstrate that such RCPNs can be used as a very effective fluorescent sensing platform for multiple DNA detection with a detection limit as low as 30 pM and a high selectivity down to single-base mismatch. The DNA detection is accomplished by the following two steps: (1) RCPN binds dye-labeled single-stranded DNA (ssDNA) probe, which brings dye and RCPN into close proximity, leading to fluorescence quenching; (2) Specific hybridization of the probe with its target generates a double-stranded DNA (dsDNA) which detaches from RCPN, leading to fluorescence recovery. It suggests that this sensing system can well discriminate complementary and mismatched DNA sequences. The exact mechanism of fluorescence quenching involved is elucidated experimentally and its use in a human blood serum system is also demonstrated successfully. PMID:22279589
Derakhshandeh, Parviz Gohari; Soleimannejad, Janet; Janczak, Jan
2015-09-01
Nanoparticles of a new two-dimensional cerium(III) coordination polymer compound, [Ce(pzdc)(pzdcH)(H2O)3]n (1), (H2pzdc=2,3-pyrazinedicarboxylic acid), have been synthesized by a sonochemical process and characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), FT-IR spectroscopy and elemental analyses. Compound 1 was structurally characterized by single crystal X-ray diffraction and was shown that it consists of 2D sheets that construct a three-dimensional supramolecular architecture via non-covalent interactions i.e. hydrogen bonding. The thermal stability of compound 1 both for its crystals and nanostructures has been studied by the thermal gravimetric (TG) method and compared with each other. The role of ultrasound irradiation power and the concentration of initial reactants on the size and morphology of the nano-structured compound 1, has been investigated. Calcination of compound 1 at 800°C under air atmosphere yields ceria nanoparticles. Furthermore, the fluorescent properties of compound 1 at room temperature were studied. PMID:25682466
NASA Astrophysics Data System (ADS)
Zhang, Qi-Long; Hu, Peng; Zhao, Yi; Feng, Guang-Wei; Zhang, Yun-Qian; Zhu, Bi-Xue; Tao, Zhu
2014-02-01
Five silver coordination polymers, namely, {[Ag(3,3?-daps)2]·BF4}n (1), {[Ag(3,3?-daps)2]·NO3}n (2), [Ag(3,3?-daps)(CF3SO3)]n (3), {[Ag(4,4?-daps)]·CF3SO3}n (4), and {[Ag(4,4?-daps)]·ClO4}n (5) (3,3?-daps=di(3?-aminodiphenyl)sulfone, and 4,4?-daps=di(4?-aminodiphenyl)sulfone) have been synthesized and structural characterized by elemental analyses, IR spectra, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction analyses. Complex 1 displays a 1D ladder-like chain with four-connected Ag ions and bridged 3,3?-daps. Complex 2 shows other 1D ladder chain modified by tentacles. Complex 3 is a 2D layer structure with both Ag ions and 3,3?-daps are 3-connected nodes. Complex 4 is another 1D ladder chain with three-connected Ag ions and 4,4?-daps. Complex 5 shows a 2D 44-sql net with Ag ions and 4,4?-daps as 4-connected nodes. Moreover, their solid state luminescence and thermal stabilities also have been investigated.
NASA Astrophysics Data System (ADS)
Gu, Jin-Zhong; Lv, Dong-Yu; Gao, Zhu-Qing; Liu, Jian-Zhao; Dou, Wei; Tang, Yu
2011-03-01
Four coordination polymers, [Zn(pda)(bpy)(H 2O)] n· nH 2O ( 1), [Cd(pda)(prz)(H 2O)] n ( 2), [Co 3( ?3-OH) 2(pda) 2(pyz)] n·2 nH 2O ( 3) and [Pr 2(pda) 3(H 2O) 2] n ( 4) (H 2pda=1,3-phenylendiacetic acid, bpy=4,4'-bipyridine, prz=piperazine and pyz=pyrazine) have been hydrothermally synthesized and characterized. Complex 1 is a 1D wheel-like chain structure, which is further extended into a 3D metal-organic supramolecular framework by H-bonds and ?- ? stacking interactions. Complex 2 is a 1D ladder-like chain structure, which is also further extended into a 3D metal-organic supramolecular framework by H-bonds. Complex 3 possess a 2D sheet structure with infrequent two pairs of double-helix chains. Complex 4 features a 3D structure. Both 1 and 2 display strong blue fluorescent emission at room temperature. Magnetic susceptibility measurements of complexes 3 and 4 exhibit antiferromagnetic interactions between the nearest metal ions, with C=9.99 and 3.43 cm 3 mol -1 K, and ?=-23.9 and -46.3 K, respectively.
NASA Astrophysics Data System (ADS)
Lu, Yingli; Zhao, Wenjie; Liu, Yu; Liu, Bin; Feng, Xing; Tan, Jinting; Li, Xia; Yang, Xuwu
2012-08-01
Five new coordination polymers, {[Cd3(bpt)2(DMF)2]·(H2O)2}n (1), [Cd(Hbpt)(bipy)0.5(H2O)]n (2), [Cd2(bpt)(phen)2Cl]n (3), {[Cu2(bpt)(phen)(?2-OH)(H2O)]·(H2O)2}n (4) and {[Mn5(Hbpt)4(phen)4(?2-OH)2(H2O)2]·(H2O)2(CH3CN)2}n (5) have been prepared through hydro(solvo)thermal reactions of H3bpt (H3bpt=biphenyl-3,4',5-tricarboxylic acid) with different pyridyl-containing auxiliary ligands (bipy=4,4'-bipyridine and phen=1,10-phenanthroline). Compound 1 represents a 3D ladder-like framework composed of rod-shaped infinite chains. In 2, the bridging ligand bipy links binuclear cadmium ions to generate a 2D layer. Compound 3 features a 1D ladder structure and further linked by ?-? stacking interaction to form a 3D supramolecular network. Compound 4 exhibits a binodal 3-connected net which features the Schlafli symbol of (4·82). Compound 5 contains trimetallic cluster and binuclear unite which are further linked by Hbpt ligand to form a 2D layer. Moreover, photoluminescent properties of compounds 1-3 were studied in the solid state. Magnetic susceptibility measurements indicate that compound 4 exhibits ferromagnetic exchange interactions, whereas compound 5 displays antiferromagnetic exchange interactions.
Liu, Qi; Yu, Lili; Wang, Ying; Ji, Yunzhou; Horvat, Josip; Cheng, Mei-Ling; Jia, Xiaoyan; Wang, Guoxiu
2013-03-18
Manganese-based layered coordination polymer ([Mn(tfbdc)(4,4'-bpy)(H2O)2], Mn-LCP) with microporous structure was synthesized by reaction of 2,3,5,6-tetrafluoroterephthalatic acid(H2tfbdc) and 4,4'-bipyridine(4,4'-bpy) with manganese(II) acetate tetrahydrate in water solution. Mn-LCP was characterized by elemental analysis, IR spectra, thermogravimetric analysis, X-ray single-crystal structure analysis, and powder X-ray diffraction. Magnetic susceptibility data from 300 to 1.8K show that there is a weak antiferromagnetic exchange between Mn(II) ions in Mn-LCP. As anode material, the Mn-LCP electrode exhibits an irreversible high capacity in the first discharge process and a reversible lithium storage capacity of up to about 390 mA h/g from the fourth cycle. It might provide a new method for finding new electrode materials in lithium-ion batteries. PMID:23461562
A novel polythreading Ag(I) coordination polymer with blue photoluminescence
Duan, Xian-Ying, E-mail: dxynumber@163.com [State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093 (China); Institute of Chemistry, Henan Academy of Sciences, Zhengzhou 450002 (China); Yao, Jing; Lu, Chang-Sheng [State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093 (China); Meng, Qing-Jin, E-mail: mengqj@nju.edu.cn [State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093 (China)
2013-04-15
One new compound, [Ag(p-bix)]{sub 3}[Ag(Hbtc){sub 2}]·2H{sub 2}O (H{sub 3}btc=1,2,4-benzenetricarboxylate, p-bix=1,4-bis(imidazol-1-ylmethyl)-benzene), has been synthesized under hydrothermal conditions and characterized by elemental analysis, IR, PXRD, luminescent analysis, and single-crystal X-ray diffraction. X-ray structural analysis revealed that 0-D unit [Ag(Hbtc){sub 2}]{sup 3?} and two kinds of 1-D linear chain [Ag(p-bix)]{sub ?}{sup +}, can be found within the crystal structure. The combination of 0-D [Ag(Hbtc){sub 2}]{sup 3?} unit and 1-D undulated chain [Ag1(p{sub 1}-bix)]{sub ?}{sup +} through weak Ag–O bond gave rise to 2-D anionic supramolecular doublelayer. Then the grids of the 2-D layer are threaded by 1-D linear cationic chain [Ag2(p{sub 2}-bix)]{sub ?}{sup +} to generate entangled 3-D architecture with unusual poly(pseudo-rotaxane)-type arrangements. Luminescent properties of the title complex were also studied in this paper. - Graphical abstract: Novel 3D polythreading supramolecular architecture was constructed, in which 1D linear cationic chains [Ag(p{sub 2}-bix)]{sub ?}{sup +} threaded into the grid of weak Ag–O bonded anionic 2D sheet. Highlights: ? Novel 1D{sup +}+2D{sup ?}?3D polythreading coordination complex was reported. ? Diverse conformations of p-bix result in different 1D [Ag(p-bix)]{sub ?}{sup +} chains. ? The title complex displayed blue photoluminescence at room temperature.
One-dimensional semiconductor nanostructures as absorber layers in solar cells.
Jayadevan, K P; Tseng, T Y
2005-11-01
The one-dimensional (1-D) nanostructures of cadmium chalcogenides (Il-VI: CdSe, CdTe), InP and GaAs (III-V), and the ternary chalcopyrites CulnS2, CulnSe2, and CulnTe2 (I-III-VI2) are the candidate semiconductors of interest as absorber layers in solar cells. In the confinement regime (approximately 1-10 nm) of these 1-D nanostructures, the electronic energy levels are quantized so that the oscillator strength and the resultant absorption of solar energy are enhanced. Moreover, the discrete energy levels effectively separate the electrons and holes at the two electrodes or at the interfaces with a polymer in a hybrid structure, so that an oriented and 1-D nanostructured absorber layer is expected to improve the conversion efficiency of solar cells. The intrinsic anisotropy of Il-VI and l-lll-VI2 crystal lattices and the progress in various growth processes are assessed to derive suitable morphological features of these 1-D semiconductor nanostructures. The present status of research in nanorod-based solar cells is reviewed and possible routes are identified to improve the performance of nanorod-based solar cells. Finally, the characteristics of nanorod-based solar cells are compared with the dye-sensitized and organic solar cells. PMID:16433410
One-dimensional transient analysis of volumetric heating for laser drilling
Zhang Chong; Salama, Islam A.; Quick, Nathaniel R.; Kar, Aravinda [Department of Mechanical, Materials and Aerospace Engineering, College of Optics and Photonics, Center for Research and Education in Optics and Lasers (CREOL), University of Central Florida, Orlando, Florida 32816-2700 (United States); Intel Corporation-Assembly and Technology Development, 5000 W. Chandler Boulevard, CH5-159, Chandler, Arizona 85226-3699 (United States); AppliCote Associates, LLC, 1445 Dolgner Place, Suite 23, Sanford, Florida 32771 (United States); College of Optics and Photonics, Center for Research and Education in Optics and Lasers (CREOL), University of Central Florida, Orlando, Florida 32816-2700 (United States)
2006-06-01
Generally laser energy is considered to interact only with the substrate surface, as in metals, where the laser beam does not propagate into the substrate beyond a very small absorption depth. There are, however, many instances, particularly for ceramics and polymers, where the laser beam can penetrate into the substrate to substantial depths depending on the laser wavelength and laser-material interaction characteristics. Specifically there are polymeric dielectrics used as multilayer electronic substrates in which a laser beam of wavelength 9.3 {mu}m can penetrate into the substrate. The laser energy interacts at the substrate surface as well as inside the substrate. This particular aspect of laser-material interactions is important in laser drilling of blind microvias in polymeric multilayer electronic substrates. A one-dimensional transient heat conduction model including vaporization parameters is constructed to analyze this behavior. The absorption coefficient of the dielectric is also considered in this model and the problem is solved analytically. The microvia drilling speed, temperature distribution in the dielectric, and the thickness of the residue along the microvia walls and at the bottom of the microvia are studied for different laser irradiation conditions. An overheated metastable state of material is found to exist inside the workpiece. The overheating parameters are calculated for various laser drilling parameters and are used to predict the onset of thermal damage and to minimize the residue.
Temperature-induced crossovers in the static roughness of a one-dimensional interface
NASA Astrophysics Data System (ADS)
Agoritsas, Elisabeth; Lecomte, Vivien; Giamarchi, Thierry
2011-03-01
At finite temperature and in presence of disorder, a one-dimensional elastic interface displays different scaling regimes at small and large lengthscales. Using a replica approach and a Gaussian variational method (GVM), we explore the consequences of a finite interface width ? on its small-lengthscale geometrical fluctuations. We compute analytically the static roughness B (r) of the interface as a function of the distance r between two points on the interface, in the specific case of short-range elasticity and random-bond disorder. We find that for a finite ? two temperature regimes exist, and we determine the corresponding different roughness regimes and their crossover lengthscales. In addition, using a directed polymer description, we study via a second GVM procedure and generic scaling arguments, a modified toy model that provides further insight on those results, which apply to experimental interfaces such as e.g. ferromagnetic domain walls in thin films, subjected to a quenched uncorrelated disorder. This work was supported in part by the Swiss SNF under MaNEP and division II.
Alborés, Pablo; Rentschler, Eva
2013-07-14
One pot reaction of hydrated chloride salts of Fe(II) and Co(II) with stoichiometric amounts of 2,2'-bipyrimidine (bpym) in a methanol-acetonitrile mixture afforded the corresponding 1D homonuclear coordination polymers, [?-(bpym)MCl2]n. Crystal structures of both complexes are isomorphous in the highly symmetric orthorhombic space group Fddd. The 1D coordination polymers are composed of almost orthogonal alternating bipyrimidine bridges linking the {MCl2} units. The magnetic behaviour of the Fe(II) compound can be well understood as a uniform S = 2 chain with an antiferromagnetic exchange interaction between metal ion sites. In the case of the Co(II) ion, also an antiferromagnetic interaction is operative along the uniform chain, while at low temperatures a long range-ordering is observed due to spin canting originating from the anisotropic behaviour of the Co(II) lowest energy Kramers doublets. PMID:23676951
Zohreh Rashidi Ranjbar; Ali Morsali
A novel mixed-ligand zinc(II) coordination polymer, {[Zn(?-4,4?-bipy)(?-3-bpdh)(H2O)2](ClO4)2·(4,4?-bipy)0.5}n (1); 3-bpdh=2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene and 4,4?-bipy=4,4?-bipyridine, has been synthesized and characterized by IR, 1HNMR and 13CNMR spectroscopy. The single crystal X-ray data of compound 1 shows that this coordination polymer grows in two dimensions by two different bridging ligands, 4,4?-bipy and 3-bpdh. Also, nano-scale of compound 1 has been synthesized by sonochemical method and characterized
Tsai, Jia-Dong; Yang, Chen-I
2014-11-01
The use of anions of 6,6'-bis(1H-tetrazol-5-yl)-2,2'-bipyridine (H2btzbp) as chelating ligands in preparing a coordination polymer is described. The synthesis, X-ray crystal structure and magnetic properties of a new Co(II) coordination polymer, [Co(btzbp)]n (1), are reported. The in situ [2 + 3] cycloaddition reaction of 6,6'-dicyano-2,2'-bipyridine with sodium azide in the presence of Co(ClO4)2 under hydrothermal conditions afforded compound 1. Structural characterization revealed that 1 features a distorted two-dimensional (2D) grid layer generated by both tetrazolate and 2,2'-bipyridyl bridges of the btzbp(2-) ligand. Variable temperature and field magnetic susceptibility measurements indicate that compound 1 exhibits spin canting with T(N) = 4.0 K and metamagnetism with H(c) = 300 G. PMID:25200595
ERIC Educational Resources Information Center
Tucker, David C.
1986-01-01
Presents an open-ended experiment which has students exploring polymer chemistry and reverse osmosis. This activity involves construction of a polymer membrane, use of it in a simple osmosis experiment, and application of its principles in solving a science-technology-society problem. (ML)
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.
Yuan, Guozan; Shan, Weilong; Liu, Bin; Rong, Lulu; Zhang, Liyan; Zhang, Hui; Wei, Xianwen
2014-07-01
Three new Mn(ii) coordination polymers, namely [Mn3L6·2H2O] (), [MnL2] (), and [MnL2·2H2O] (), were prepared by solvothermal reactions of Mn(ii) salts with a bispyridyl-based quinolinate ligand. All complexes were characterized by elemental analysis, IR spectra, powder and single-crystal X-ray crystallography. Single crystal X-ray studies show that these coordination polymers exhibit a structural diversification due to the different counteranions (OAc(-), Cl(-), and NO3(-)). Complex has a 2D supramolecular structure with a cyclic tetramer Mn3L6 secondary building unit. Complex possesses a rhombohedral grid network containing a type of meso-helical chain (P + M) constructed via the metal-ligand coordination interaction. Complex features a 3D non-porous structure based on the arrangement of 2D grids. Magnetic susceptibility measurements indicate that the three Mn(ii) polymers show disparate magnetic properties due to their different supramolecular structures. PMID:24846494
One-dimensional shock wave interaction with rubber and low-porosity foam
NASA Astrophysics Data System (ADS)
Yasuhara, M.; Kitagawa, K.; Sakashita, S.; Tsuzaki, Y.; Watanabe, S.
1995-06-01
One-dimensional interaction between a planar shock wave and a rubber or low-porosity foam is investigated experimentally and numerically. The considered polyurethane foam is of high density ( ? c=290 kg/m3) and lowporosity (?=0.76), and this corresponds to an intermediate condition between rubber and high-porosity foam. Stress-strain relations for the low-porosity foam are investigated by machine tests, which show larger deformation against compressive force and higher non-linearity in stress-strain curve as compared with rubber. Also the low-porosity foam shows a hysteresis cycle. Experiments on shock wave-foam interactions are conducted by using a shock tube. Experimental time history of the surface stress of the foam at the end of the shock tube does not show shock type stress increase, but continuous excessive stress rise can be seen, and then dumping vibration approaching to gas dynamic pressure of the reflected shock wave is followed, and the highest stress amounts about 3˜4 times of the pressure after the reflected gas dynamic shock wave. Interactive motions of gas and the low-porosity foam are analyzed using the Lagrangean coordinates system. An elastic model for a low-porosity foam is assumed to be a single elastic material with the measured stress-strain relation. Results of numerical simulations are compared with the shock tube experiments, which show essentially same stress variations with experimental results.
Cao, Ke-Li; Zhang, Yi-Ping; Cai, Yi-Ni; Xu, Xiao-Wei; Feng, Yun-Long, E-mail: sky37@zjnu.cn
2014-07-01
To investigate the influence of hydrogen bonds and secondary ligands on the structures and properties of the resulting frameworks, five new Co(II) compounds have been synthesized by the reactions of Co(II) salts and 3,5-bis(pyridin-4-ylmethoxy)benzoic acid (HL) with four rationally selected dicarboxylic acid ligands. Without secondary ligand, we got one compound [CoL{sub 2}(H{sub 2}O){sub 2}]{sub n}·2nH{sub 2}O (1), which possesses a 1D chain structure. In the presence of ancillary ligands, namely, 1,3-adamantanedicarboxylic acid (H{sub 2}adbc), terephthalic acid (H{sub 2}tpa), thiophene-2,5-dicarboxylic acid (H{sub 2}tdc) and 1,4-benzenedithioacetic acid (H{sub 2}bdtc), four 3D structures [Co{sub 2}L{sub 2}(adbc)]{sub n}·nH{sub 2}O (2), [Co{sub 2}L{sub 2}(tpa)]{sub n} (3), [Co{sub 2}L{sub 2}(tdc)]{sub n} (4), [Co{sub 2}L{sub 2}(bdtc)(H{sub 2}O)]{sub n} (5) were obtained, respectively. It can be observed from the architectures of 1–5 that hydrogen bonds and secondary ligands both have great effects on the spatial connective fashions, resulting in the formation of various dimensional compounds. The XRPD, TGA data of title polymers and the magnetic properties for 2 and 5 have also been investigated. - Graphical abstract: The structural differences show that the ancillary ligands have great effects on the spatial connective fashions, resulting in the formation of various dimensional compounds. - Highlights: • Five new Co(II) coordination polymers have been synthesized by solvothermal reactions based on 3,5-bis(pyridin-4-ylmethoxy)benzoic acid (HL). • The long-flexible ligand (HL) is a good candidate to produce interpenetrating architectures. • The secondary dicarboxylic acid ligands play important roles in the spatial connective fashions and the formation of various dimensional compounds. • The magnetism studies show that both 2 and 5 exhibit antiferromagnetic interactions.
NASA Astrophysics Data System (ADS)
Shi, Ling; Yang, Ping; Huang, Guang; Li, Qian; Wang, Ning; Wu, Jian-Zhong; Yu, Ying
2011-07-01
Two mixed-valence Cu ICu II coordination polymers [Cu ICu II(qdiol)ClL] n (qdiol 2-=2,3-dioxyquinoxalinate, L=2,2'-bipyridine, 1; L=1,10-phenanthroline, 2) were obtained in basic ethanolic solution of CuCl 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 II, qdiol 2- and L are identical in both complexes. But the Cu I ions are two- and three-coordinated, and the Cl - 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 temperature 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.
Deshmukh, Milind Madhusudan; Ohba, Masaaki; Kitagawa, Susumu; Sakaki, Shigeyoshi
2013-03-27
Absorption of CO2 and CS2 molecules into the Hofmann-type three-dimensional porous coordination polymer (PCP) {Fe(Pz)[Pt(CN)4]}n (Pz = pyrazine) was theoretically explored with the ONIOM(MP2.5 or SCS-MP2:DFT) method, where the M06-2X functional was employed in the DFT calculations. The binding energies of CS2 and CO2 were evaluated to be -17.3 and -5.2 kcal mol(-1), respectively, at the ONIOM(MP2.5:M06-2X) level and -16.9 and -4.4 kcal mol(-1) at the ONIOM(SCS-MP2:M06-2X) level. It is concluded that CS2 is strongly absorbed in this PCP but CO2 is only weakly absorbed. The absorption positions of these two molecules are completely different: CO2 is located between two Pt atoms, whereas one S atom of CS2 is located between two Pz ligands and the other S atom is between two Pt atoms. The optimized position of CS2 agrees with the experimentally reported X-ray structure. To elucidate the reasons for these differences, we performed an energy decomposition analysis and found that (i) both the large binding energy and the absorption position of CS2 arise from a large dispersion interaction between CS2 and the PCP, (ii) the absorption position of CO2 is mainly determined by the electrostatic interaction between CO2 and the Pt moiety, and (iii) the small binding energy of CO2 comes from the weak dispersion interaction between CO2 and the PCP. Important molecular properties relating to the dispersion and electrostatic interactions, which are useful for understanding and predicting gas absorption into PCPs, are discussed in detail. PMID:23437824
NASA Astrophysics Data System (ADS)
Zhang, Kou-Lin; Zhang, Jing-Bo; Jing, Chu-Yue; Zhang, Lei; Walton, Richard I.; Zhu, Peizhi; Ng, Seik Weng
2014-03-01
Four 2D coordination polymers (CPs) with different structures containing the multifunctional ligand 5-hydroxyisophthalate (5-OH-BDC2-), [Zn(5-OH-BDC)(btb)]·2H2O (1), [Cd(5-OH-BDC)(btp)(H2O)]·3H2O (2), [Cd(5-OH-BDC)(bth)2(H2O)]·H2O (3) and [Pb(5-OH-BDC)]·H2O (4) [btp=1, 3-bis(1,2,4-triazol-1-yl)propane, btb=1,4-bis(1,2,4-triazol-1-yl)butane, bth=1, 6-bis(1,2,4-triazol-1-yl)hexane] were obtained. 1-3 were synthesised hydrothermally, while 4 was obtained under ambient condition. The adjacent (2D?2D) polycatenated 2D layers of 1 polythread in a parallel manner to form an unusual 2D?3D polythreaded framework. 2 contains an undulated 2D (4, 4) network and further extends into an "embracing" double-layer structure through the C-H···? and ?···? stacking interactions. 3 exhibits a non-interpenetrating 2D (4, 4)-network. 4 exhibits a 2D double-layered binodal (4, 4)-net containing oblong nanochannels with symbol (4363)2. Reversible dehydration-rehydration is observed in 1, 2 and 4, which fall within the category of "recoverable collapsing" and "guest-induced re-formation" frameworks, while 3 exhibits irreversible dehydration-rehydration behaviour. The solid state fluorescent properties of 1-4 have been investigated.
Han, Min-Le; Duan, Ya-Ping; Li, Dong-Sheng; Xu, Guo-Wang; Wu, Ya-Pan; Zhao, Jun
2014-12-14
Five new coordination polymers, namely, [Mn(2,2?-bipy)(H2O)2(H2L1)]n (1), {[Co(btb)(H2O)2(H2L1)]·0.5H2O}n (2), [Co(bib)(H2O)2(H2L1)]n (3), [Ni2(bpm)(H2O)3(L2)]n (4), and {[Co2(H2O)3(OH)(HL2)]·H2O}n (5), (H4L1 = 1,1?:2?,1??-terphenyl-4,4?,4??,5?-tetracarboxylic acid, H4L2 = 1,1?:2?,1??-terphenyl-3,3??,4?,5?-tetracarboxylic acid, 2,2?-bipy = 2,2?-bipyridine, btb = 1,4-bis(1,2,4-triazol-1-yl)butane, bib = 1,4-bis(imidazol-1-yl)butane, bpm = bis(4-pyridyl)amine), have been obtained under hydrothermal conditions. Complex 1 exhibits a 3D supramolecular framework based on 1D chains. Both complexes 2 and 3 are 3D supramolecular frameworks constructed from 1D zig-zag chains. Complex 4 features a 3D tetra-nodal (3,4,4,5)-connected architecture containing 1D ?-COO bridged chains with (5(2)·6(2)·7.9)(5(2)·6(4)·7(3)·8)2(5(2)·6)2(6(3)·7(2)·9) topology. Complex 5 shows a 3D penta-nodal (3,4,4,6,6)-connected net containing 1D ?-OH/?-COO bridged chains and mononuclear Co(II) nodes with a (4(2)·6(3)·8)(4(3))2(4(4)·6(2))2(4(4)·6(6)·8(5))2(4(4)·6(7)·8(4)) topology. Variable-temperature magnetic susceptibility measurements reveal that complexes 2 and 3 show antiferromagnetic interactions between the adjacent Co(II) ions, whereas 4 is a ferromagnetic system. PMID:25347690
Odd-frequency superconductivity on quasi-one-dimensional triangular lattice in the Hubbard model
NASA Astrophysics Data System (ADS)
Shigeta, K.; Onari, S.; Yada, K.; Tanaka, Y.
2009-10-01
We study the superconductivity in the Hubbard model on quasi-one-dimensional triangular lattice using random phase approximation (RPA). We find that odd-frequency spin-singlet p-wave pairing can be realized on isosceles quasi-one-dimensional triangular lattice.
Quasi-one-dimensional anisotropic Heisenberg model in a transverse magnetic field
NASA Astrophysics Data System (ADS)
Dmitriev, D. V.; Krivnov, V. Ya.
2004-09-01
The phase diagram of weakly coupled $XXZ$ chains in a transverse magnetic field is studied using the mean-field approximation for the interchain coupling and known exact results for an effective one-dimensional model. Results are applied to the quasi-one-dimensional antiferromagnet $Cs_{2}CoCl_{4}$ and the value of interchain interaction in this compound is estimated.
An Aggregation Model Reduction Method for One-Dimensional Distributed Systems
Skogestad, Sigurd
An Aggregation Model Reduction Method for One-Dimensional Distributed Systems Andreas Linhart Engineers AIChE J, 58: 15241537, 2012 Keywords: model reduction, dynamic simulation, distributed systems models of spatially discrete or continuous one- dimensional distributed parameter systems. The reduced
SYSTEMS OF ONE-DIMENSIONAL RANDOM WALKS IN A COMMON RANDOM ENVIRONMENT
Peterson, Jonathon
SYSTEMS OF ONE-DIMENSIONAL RANDOM WALKS IN A COMMON RANDOM ENVIRONMENT JONATHON PETERSON Abstract. We consider a system of independent one-dimensional random walks in a common random environment under-dimensional random walks in a common random environment. We modify the standard notion of random walks in random
Initial-boundary Value Problems to the One-dimensional Compressible Navier-Stokes
Initial-boundary Value Problems to the One-dimensional Compressible Navier-Stokes Equations to the initial-boundary value problems of the one-dimensional compress- ible Navier-Stokes equations-dimensional compressible Navier-Stokes equations; initial- boundary value problems; global solutions with large data
VANISHING VISCOSITY LIMIT TO RAREFACTION WAVES FOR THE NAVIER-STOKES EQUATIONS OF ONE-DIMENSIONAL
of the Navier-Stokes equations for one-dimensional compress- ible heat-conducting fluids with centered of the corresponding Euler equations uniformly away from the initial discontinuity. Key words. Compressible Navier-Stokes for the Navier-Stokes equations for a one-dimensional compressible heat-conducting fluid (in Lagrangian
Growth of anisotropic one-dimensional ZnS nanostructures{ Daniel Moore and Zhong L. Wang*
Wang, Zhong L.
Growth of anisotropic one-dimensional ZnS nanostructures{ Daniel Moore and Zhong L. Wang* Received with wurtzite ZnS. This feature article covers the ZnS one-dimensional nanostructures that have been synthesized14 ZnS is a direct wide bandgap (3.91 eV) compound semiconductor with a high index of refraction
Data Structures For One-Dimensional Packet Classification Using Most-Specific-Rule Matching
Sahni, Sartaj K.
Data Structures For One-Dimensional Packet Classification Using Most-Specific-Rule Matching structures that have been proposed for one-dimensional packet classification. Our review is limited to data is conflict free. Data structures for both static and dynamic rule tables are dis- cussed. Keywords: Packet
A one-dimensional analytical model for airborne contaminant transport in airliner cabins
Chen, Qingyan "Yan"
A one-dimensional analytical model for airborne contaminant transport in airliner cabins Sagnik-dimensional analytical model that can predict the longitudinal transmission of airborne contaminants or disease viruses in the model. The analytical solution for the one-dimensional contaminant transport model is obtained by using
The rigged Hilbert space of the algebra of the one-dimensional rectangular barrier potential
NASA Astrophysics Data System (ADS)
de la Madrid, Rafael
2004-08-01
The rigged Hilbert space of the algebra of the one-dimensional rectangular barrier potential is constructed. The one-dimensional rectangular potential provides another opportunity to show that the rigged Hilbert space fully accounts for Dirac's bra-ket formalism. The analogy between Dirac's formalism and Fourier methods is pointed out.
BV Solutions of the One-dimensional Perona-Malik Equation
March, Riccardo
BV Solutions of the One-dimensional Perona-Malik Equation Riccardo March Istituto per le) Abstract We consider the one-dimensional Perona-Malik equation of nonlinear diffu- sion. The Perona-Malik in the framework of nonlinear filtering of signals. In any case the Perona- Malik equation is a formally ill
Velocity and diffusion coefficient of a random asymmetric one-dimensional hopping model
Paris-Sud XI, UniversitÃ© de
899 Velocity and diffusion coefficient of a random asymmetric one-dimensional hopping model C hopping rates are calculated in a simple way through a recursion relation method, which allows of drift and diffusion on one-dimensional lattices with random asymmetric hopping rates has recently
Parameter-dependent thermal conductivity of one-dimensional 4 Nianbei Li1
Li, Baowen
Parameter-dependent thermal conductivity of one-dimensional 4 lattice Nianbei Li1 and Baowen Li1 the thermal conductivity of a one-dimensional 4 lattice with strong on-site harmonic potential. The expression for the thermal conductivity in terms of different parameters is derived from the effective phonon theory