Diamond detectors for high-temperature transactinide chemistry experiments
NASA Astrophysics Data System (ADS)
Steinegger, Patrick; Dressler, Rugard; Eichler, Robert; Piguet, Dave; Streuli, Silvan; Türler, Andreas
2017-04-01
Here, we present the fabrication details and functional tests of diamond-based α-spectroscopic sensors, dedicated for high-temperature experiments, targeting the chemistry of transactinide elements. Direct heating studies with this sensor material, revealed a current upper temperature threshold for a safe α-spectroscopic operation of Tdet = 453 K . Up to this temperature, the diamond sensor could be operated in a stable manner over long time periods of the order of days. A satisfying resolution of ≈ 50 keVFWHM was maintained throughout all conducted measurements. However, exceeding the mentioned temperature limit led to a pronounced spectroscopic degradation in the range of 453 - 473 K , thereby preventing any further α-spectroscopic application. These findings are in full agreement with available literature data. The presented detector development generally enables the chemical investigation of more short-lived and less volatile transactinide elements and their compounds, yet unreachable with the currently employed silicon-based solid state sensors. In a second part, the design, construction, and α-spectroscopic performance of a 4-segmented diamond detector, dedicated and used for transactinide element research, is given as an application example.
Chemical experiments with superheavy elements.
Türler, Andreas
2010-01-01
Unnoticed by many chemists, the Periodic Table of the Elements has been extended significantly in the last couple of years and the 7th period has very recently been completed with eka-Rn (element 118) currently being the heaviest element whose synthesis has been reported. These 'superheavy' elements (also called transactinides with atomic number > or = 104 (Rf)) have been artificially synthesized in fusion reactions at accelerators in minute quantities of a few single atoms. In addition, all isotopes of the transactinide elements are radioactive and decay with rather short half-lives. Nevertheless, it has been possible in some cases to investigate experimentally chemical properties of transactinide elements and even synthesize simple compounds. The experimental investigation of superheavy elements is especially intriguing, since theoretical calculations predict significant deviations from periodic trends due to the influence of strong relativistic effects. In this contribution first experiments with hassium (Hs, atomic number 108), copernicium (Cn, atomic number 112) and element 114 (eka-Pb) are reviewed.
Chemical properties of the transactinide elements studied inliquid phase with SISAK
DOE Office of Scientific and Technical Information (OSTI.GOV)
Omtvedt, J.P.; Alstad, J.; Bjornstad, T.
2007-05-01
This article starts with a review of the current SISAKliquid-liquid extraction system, as used after the physical preseparatorBGS at LBNL for chemical studies of transactinide elements. Emphasis willbe on new additions and developments. Then the possibilities offered bythe new TASCA separator at GSI and the use of actinide targets at bothGSI and LBNL are discussed with respect to future SISAK transactinideexperiments. Finally, current and future liquid-liquid extraction systemsfor studying elements Rf up to Hs are discussed.
NASA Astrophysics Data System (ADS)
Even, J.; Ballof, J.; Brüchle, W.; Buda, R. A.; Düllmann, Ch. E.; Eberhardt, K.; Gorshkov, A.; Gromm, E.; Hild, D.; Jäger, E.; Khuyagbaatar, J.; Kratz, J. V.; Krier, J.; Liebe, D.; Mendel, M.; Nayak, D.; Opel, K.; Omtvedt, J. P.; Reichert, P.; Runke, J.; Sabelnikov, A.; Samadani, F.; Schädel, M.; Schausten, B.; Scheid, N.; Schimpf, E.; Semchenkov, A.; Thörle-Pospiech, P.; Toyoshima, A.; Türler, A.; Vicente Vilas, V.; Wiehl, N.; Wunderlich, T.; Yakushev, A.
2011-05-01
Performing experiments with transactinide elements demands highly sensitive detection methods due to the extremely low production rates (one -atom -at -a -time conditions). Preseparation with a physical recoil separator is a powerful method to significantly reduce the background in experiments with sufficiently long-lived isotopes ( t1/2≥0.5 s). In the last years, the new gas-filled TransActinide Separator and Chemistry Apparatus (TASCA) was installed and successfully commissioned at GSI. Here, we report on the design and performance of a Recoil Transfer Chamber (RTC) for TASCA—an interface to connect various chemistry and counting setups with the separator. Nuclear reaction products recoiling out of the target are separated according to their magnetic rigidity within TASCA, and the wanted products are guided to the focal plane of TASCA. In the focal plane, they pass a thin Mylar window that separates the ˜1 mbar atmosphere in TASCA from the RTC kept at ˜1 bar. The ions are stopped in the RTC and transported by a continuous gas flow from the RTC to the ancillary setup. In this paper, we report on measurements of the transportation yields under various conditions and on the first chemistry experiments at TASCA—an electrochemistry experiment with osmium and an ion exchange experiment with the transactinide element rutherfordium.
Chemistry and materials science progress report, FY 1994
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1995-07-01
Research is reported in the areas of surface science, fundamentals of the physics and processing of metals, energetic materials, transactinide materials and properties and other indirectly related areas of weapons research.
ERIC Educational Resources Information Center
Seaborg, Glenn T.
1983-01-01
Reviews the historical development of the periodic table, examining major changes due to understanding of radioactivity, synthetic transmutation by bombardment, differences between transuranium elements and the lanthanide series, and the transactinide elements. Discusses the continuing work on atomic synthesis and its importance in extending our…
NASA Astrophysics Data System (ADS)
Wegrzecki, Maciej; Bar, Jan; Budzyński, Tadeusz; CieŻ, Michal; Grabiec, Piotr; Kozłowski, Roman; Kulawik, Jan; Panas, Andrzej; Sarnecki, Jerzy; Słysz, Wojciech; Szmigiel, Dariusz; Wegrzecka, Iwona; Wielunski, Marek; Witek, Krzysztof; Yakushev, Alexander; Zaborowski, Michał
2013-07-01
The paper discusses the design of charged-particle detectors commissioned and developed at the Institute of Electron Technology (ITE) in collaboration with foreign partners, used in international research on transactinide elements and to build personal radiation protection devices in Germany. Properties of these detectors and the results obtained using the devices are also presented. The design of the following epiplanar detector structures is discussed: ♢ 64-element chromatographic arrays for the COMPACT (Cryo On-line Multidetector for Physics And Chemistry of Transactinides) detection system used at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt (GSI) for research on Hassium, Copernicium and Flerovium, as well as elements 119 and 120, ♢ 2-element flow detectors for the COLD (Cryo On-Line Detector) system used for research on Copernicium and Flerovium at the Joint Institute for Nuclear Research, Dubna, ♢ detectors for a radon exposimeter and sensors for a neutron dosimeter developed at the Institut für Strahlenschutz, Helmholtz Zentrum München. The design of planar detectors - single-sided and double-sided strip detectors for the Focal Plane Detector Box used at GSI for research on Flerovium and elements 119 and 120 is also discussed.
The generator coordinate Dirac-Fock method for open-shell atomic systems
NASA Astrophysics Data System (ADS)
Malli, Gulzari L.; Ishikawa, Yasuyuki
1998-11-01
Recently we developed generator coordinate Dirac-Fock and Dirac-Fock-Breit methods for closed-shell systems assuming finite nucleus and have reported Dirac-Fock and Dirac-Fock-Breit energies for the atoms He through Nobelium (Z=102) [see Refs. Reference 10Reference 11Reference 12Reference 13]. In this paper, we generalize our earlier work on closed-shell systems and develop a generator coordinate Dirac-Fock method for open-shell systems. We present results for a number of representative open-shell heavy atoms (with nuclear charge Z>80) including the actinide and superheavy transactinide (with Z>103) atomic systems: Fr (Z=87), Ac (Z=89), and Lr (Z=103) to E113 (eka-thallium, Z=113). The high accuracy obtained in our open-shell Dirac-Fock calculations is similar to that of our closed-shell calculations, and we attribute it to the fact that the representation of the relativistic dynamics of an electron in a spherical ball finite nucleus near the origin in terms of our universal Gaussian basis set is as accurate as that provided by the numerical finite difference method. The DF SCF energies calculated by Desclaux [At. Data. Nucl. Data Tables 12, 311 (1973)] (apart from a typographic error for Fr pointed out here) are higher than those reported here for atoms of some of the superheavy transactinide elements by as much as 5 hartrees (136 eV). We believe that this is due to the use by Desclaux of much larger atomic masses than the currently accepted values for these elements.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Malli, Gulzari L., E-mail: malli@sfu.ca
2015-02-14
Our ab initio all-electron fully relativistic Dirac–Fock (DF) and nonrelativistic (NR) Hartree-Fock calculations predict the DF relativistic and NR energies for the reaction: Sg + 6 CO → Sg(CO){sub 6} as −7.39 and −6.96 eV, respectively, i.e., our calculated ground state total DF relativistic and NR energies for the reaction product Sg(CO){sub 6} are lower by 7.39 and 6.96 eV than the total DF and NR ground state energies of the reactants, viz., one Sg atom plus six CO molecules, respectively. Our calculated DF relativistic and NR atomization energies (Ae) are 65.23 and 64.82 eV, respectively, and so the contributionmore » of relativistic effects to the Ae of ∼0.40 eV is marginal. The Sg–C and C–O optimized bond distances for the octahedral geometry as calculated in our DF (NR) calculations are 2.151 (2.318 Å) and 1.119 (1.114 Å), respectively. The BSSE correction calculated using the DIRAC code ∼14 kcal/mol. The relativistic DF and NR mean energies predicted by us are 118.8 and 111.9 kJ/mol, respectively, and the contribution of ∼7 kJ/mol due to relativistic effects to the mean energy of Sg(CO){sub 6} is negligible. Ours are the first calculations of the relativistic effects for the atomization energy, mean bond energy, and energy of the reaction for possible formation of Sg(CO){sub 6}, and both our relativistic DF and the NR treatments clearly predict for the first time the existence of hexacarbonyl of the transactinide superheavy element seaborgium Sg. In conclusion, relativistic effects are not significant for Sg(CO){sub 6}.« less
Odd-Z Transactinide Compound Nucleus Reactions Including the Discovery of 260Bh
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nelson, Sarah L.
Several reactions producing odd-Z transactinide compound nuclei were studiedwith the 88-Inch Cyclotron and the Berkeley Gas-Filled Separator at the Lawrence Berkeley National Laboratory. The goal was to produce the same compound nucleus ator near the same excitation energy with similar values of angular momentum via differentnuclear reactions. In doing so, it can be determined if there is a preference in entrancechannel, because under these experimental conditions the survival portion of Swiatecki, Siwek-Wilcznska, and Wilczynski's"Fusion By Diffusion" model is nearly identical forthe two reactions. Additionally, because the same compound nucleus is produced, theexit channel is the same. Four compound nuclei were examined in this study: 258Db, 262Bh, 266Mt, and 272Rg. These nuclei were produced by using very similar heavy-ion induced-fusion reactions which differ only by one proton in the projectile or target nucleus (e.g.: 50Ti + 209Bi vs. 51V + 208Pb). Peak 1n exit channel cross sections were determined for each reaction in each pair, and three of the four pairs' cross sections were identical within statistical uncertainties. This indicates there is not an obvious preference of entrancechannel in these paired reactions. Charge equilibration immediately prior to fusionleading to a decreased fusion barrier is the likely cause of this phenomenon. In addition to this systematic study, the lightest isotope of element 107, bohrium, was discovered in the 209Bi( 52Cr,n) reaction. 260Bh was found to decay by emission of a 10.16 MeV alpha particle with a half-life of 35more » $$+19\\atop{-9}$$ ms. The cross section is 59 pb at an excitation energy of 15.0 MeV. The effect of the N = 152 shell is also seen in this isotope's alpha particle energy, the first evidence of such an effect in Bh. All reactions studied are also compared to model predictions by Swiatecki, Siwek-Wilcznska, and Wilczynski 's" Fusion By Diffusion " theory.« less
Despotopulos, John D.; Kmak, Kelly N.; Gharibyan, Narek; ...
2015-10-01
Here, new procedures have been developed to isolate no-carrier-added (NCA) radionuclides of the homologs and pseudo-homologs of flerovium (Hg, Sn) and element 115 (Sb), produced by 12–15 MeV proton irradiation of foil stacks with the tandem Van-de-Graaff accelerator at the Lawrence Livermore National Laboratory Center for Accelerator Mass Spectrometry (CAMS) facility. The separation of 113Sn from natIn foil was performed with anion-exchange chromatography from hydrochloric and nitric acid matrices. A cation-exchange chromatography method based on hydrochloric and mixed hydrochloric/hydroiodic acids was used to separate 124Sb from natSn foil. A procedure using Eichrom TEVA resin was developed to separate 197Hg frommore » Au foil. These results demonstrate the suitability of using the CAMS facility to produce NCA radioisotopes for studies of transactinide homologs.« less
NASA Astrophysics Data System (ADS)
Skarnemark, Gunnar; Allard, Stefan; Ekberg, Christian; Nordlund, Anders
2009-08-01
The need for engineers and scientists who can ensure safe and secure use of nuclear energy is large in Sweden and internationally. Chalmers University of Technology is therefore launching a new 2-year master's program in Nuclear Engineering, with start from the autumn of 2009. The program is open to Swedish and foreign students. The program starts with compulsory courses dealing with the basics of nuclear chemistry and physics, radiation protection, nuclear power and reactors, nuclear fuel supply, nuclear waste management and nuclear safety and security. There are also compulsory courses in nuclear industry applications and sustainable energy futures. The subsequent elective courses can be chosen freely but there is also a possibility to choose informal tracks that concentrate on nuclear chemistry or reactor technology and physics. The nuclear chemistry track comprises courses in e.g. chemistry of lanthanides, actinides and transactinides, solvent extraction, radioecology and radioanalytical chemistry and radiopharmaceuticals. The program is finished with a one semester thesis project. This is probably a unique master program in the sense of its combination of deep courses in both nuclear technology and nuclear chemistry.
Foreword [Special Issue on Superheavy Elements
Düllmann, Christoph E.; Herzberg, Rolf -Dietmar; Nazarewicz, Witold; ...
2015-12-07
Reflecting the breadth of research opportunities in the field of superheavy element research, this special issue covers the range of topics in a comprehensive way, including synthesis of superheavy isotopes, nuclear structure, atomic shell structure, and chemical properties. The contributions detail the status of the field and lay out perspectives for the future. The prospects are bright: new isotopes are awaiting discovery, completing the landscape of superheavy nuclei and bridging the currently existing gap between nuclei synthesized in cold fusion reactions and those from 48Ca induced fusion reactions. The possibility that the limits of nuclear structure studies can be pushedmore » even further in mass and charge has greatly motivated a number of new facilities. Advances in experimental techniques will allow studies on isotopes produced significantly below the 1 pb level. Chemical studies progressing to elements never studied to date are already being prepared. Ultra-fast chemistry setups are under development and it will be fascinating to see them at work, elucidating the influence of relativistic effects on superheavy elements. The richness of chemical systems available for transactinides will expand further, giving access to new chemical systems, giving more information on the architecture of the periodic table.« less
32-element beta detector developed at the Institute of Electron Technology (ITE)
NASA Astrophysics Data System (ADS)
Wegrzecki, Maciej; Yakushev, Alexander; Bar, Jan; Budzyński, Tadeusz; Grabiec, Piotr; Kłos, Helena; Panas, Andrzej; Słysz, Wojciech; Stolarski, Maciej; Szmigiel, Dariusz; Wegrzecka, Iwona; Zaborowski, Michał
2014-08-01
The paper presents the design, technology and parameters of a new .silicon detector for detection of electrons (below named as beta detector) developed at the Institute of Electron Technology (ITE). The detector will be used for research on transactinide elements at the GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt (GSI). The detector consists of a monolithic 32-element array with an active area diameter of 90 mm and a thickness of 0.9 mm. The starting material is a high-resistivity ν silicon wafer (5 kΩcm resistivity). 32 planar p+-ν junctions are formed by boron diffusion on the top side of the wafer. On the bottom side, an n+ region, which forms a common cathode, is formed on the entire surface by phosphorus diffusion. The array is mounted on a special epoxy-glass laminate substrate, copper-clad on both sides. Two model detectors have been fabricated and studied. Very good electrical parameters have been achieved. For the first array, with supply voltage VR = 20 V, the minimum dark current was 8 nA, the maximum dark current 97.1 nA, and the average dark current 25.1 nA. For the second array, it was 11.5 nA, 378.8 nA and 40.0 nA respectively.
Chemistry of the superheavy elements.
Schädel, Matthias
2015-03-13
The quest for superheavy elements (SHEs) is driven by the desire to find and explore one of the extreme limits of existence of matter. These elements exist solely due to their nuclear shell stabilization. All 15 presently 'known' SHEs (11 are officially 'discovered' and named) up to element 118 are short-lived and are man-made atom-at-a-time in heavy ion induced nuclear reactions. They are identical to the transactinide elements located in the seventh period of the periodic table beginning with rutherfordium (element 104), dubnium (element 105) and seaborgium (element 106) in groups 4, 5 and 6, respectively. Their chemical properties are often surprising and unexpected from simple extrapolations. After hassium (element 108), chemistry has now reached copernicium (element 112) and flerovium (element 114). For the later ones, the focus is on questions of their metallic or possibly noble gas-like character originating from interplay of most pronounced relativistic effects and electron-shell effects. SHEs provide unique opportunities to get insights into the influence of strong relativistic effects on the atomic electrons and to probe 'relativistically' influenced chemical properties and the architecture of the periodic table at its farthest reach. In addition, they establish a test bench to challenge the validity and predictive power of modern fully relativistic quantum chemical models. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
Measurement of the first ionization potential of lawrencium, element 103.
Sato, T K; Asai, M; Borschevsky, A; Stora, T; Sato, N; Kaneya, Y; Tsukada, K; Düllmann, Ch E; Eberhardt, K; Eliav, E; Ichikawa, S; Kaldor, U; Kratz, J V; Miyashita, S; Nagame, Y; Ooe, K; Osa, A; Renisch, D; Runke, J; Schädel, M; Thörle-Pospiech, P; Toyoshima, A; Trautmann, N
2015-04-09
The chemical properties of an element are primarily governed by the configuration of electrons in the valence shell. Relativistic effects influence the electronic structure of heavy elements in the sixth row of the periodic table, and these effects increase dramatically in the seventh row--including the actinides--even affecting ground-state configurations. Atomic s and p1/2 orbitals are stabilized by relativistic effects, whereas p3/2, d and f orbitals are destabilized, so that ground-state configurations of heavy elements may differ from those of lighter elements in the same group. The first ionization potential (IP1) is a measure of the energy required to remove one valence electron from a neutral atom, and is an atomic property that reflects the outermost electronic configuration. Precise and accurate experimental determination of IP1 gives information on the binding energy of valence electrons, and also, therefore, on the degree of relativistic stabilization. However, such measurements are hampered by the difficulty in obtaining the heaviest elements on scales of more than one atom at a time. Here we report that the experimentally obtained IP1 of the heaviest actinide, lawrencium (Lr, atomic number 103), is 4.96(+0.08)(-0.07) electronvolts. The IP1 of Lr was measured with (256)Lr (half-life 27 seconds) using an efficient surface ion-source and a radioisotope detection system coupled to a mass separator. The measured IP1 is in excellent agreement with the value of 4.963(15) electronvolts predicted here by state-of-the-art relativistic calculations. The present work provides a reliable benchmark for theoretical calculations and also opens the way for IP1 measurements of superheavy elements (that is, transactinides) on an atom-at-a-time scale.
Synthesis reactions and radioactive properties of transactinoid elements
NASA Astrophysics Data System (ADS)
Oganessian, Yu. Ts.
1994-10-01
It is well known that the heaviest elements of the periodic table have been synthesized in the cold fusion of magic nuclei of Pb with Z less than 26 ions. Because of dynamic limitations for fusion under strong Coulomb interaction of nuclei, the cross-sections of cold fusion reactions diminish exponentially with growing compound nucleus atomic number. For element Z = 110 produced in the reaction Pb-208(Ni-62,n)(sub 271)110, the expected cross-section is 10(exp -36) sq cm. In still more asymmetric reactions, when isotopes of actinoid elements irradiated with relatively light ions (Z less than or equal 12) are used as the target material, the compound nuclei possess an excitation energy of approx. 50 MeV. At this energy the nuclear shell effects are strongly suppressed and, as a result, in the case of hot compound nuclei of transactinoid elements the fission barrier is practically absent. The transition of these nuclei into the ground state depends strongly on the dynamic properties of the system with respect to the fission degree of freedom. Experimental studies were going on in two directions: (1) determination of the fission time by measuring the prefission neutrons (of Cf-Fm nuclei) in a wide interval of excitation energies; (2) direct synthesis of known nuclides with Z = 102-105 in reactions with ions of Ne-22, Mg-26, Al-27 and P-31 when final nuclei are produced in the ground state after the evaporation of five or six neutrons from the excited compound nuclei (E(sub x) = 50-60 MeV). The dependence of the reaction cross-section (HI, 5-6n) on the atomic number of the compound nucleus in different target-ion combinations points to the possibility of synthesizing new elements in hot fusion reactions. The advantage of these reactions arises from the use of neutron-rich nuclei like Cm-248 and Cf-249 which allows us to synthesize nuclei close to the deformed shell N = 162, for which a considerable growth of stability against spontaneous fission is predicted. Experimental set-ups and methods of detecting rare events of formation and decay of transactinide nuclei are described.
Essential Trends in Inorganic Chemistry (by D. M. P. Mingos)
NASA Astrophysics Data System (ADS)
Phillips, Reviewed By David A.
2000-05-01
The author has chosen to present his material in a distinctly different fashion from that of most inorganic chemistry textbook writers. Most texts are a mix of theory chapters and descriptive chapters, with the latter focusing on specific groups of elements. However, after a chapter laying out the quantum mechanical basis of the periodic table, Mingos has elected to organize the remaining chapters around vertical, horizontal, and diagonal relationships, or on isoelectronic and isostoichiometric relationships. I think this approach has worked remarkably well. Chapters 2-5 contain a wealth of information accompanied by clear, coherent discussions of the underlying principles that account for the observed trends and anomalies. Every serious inorganic chemist should have a copy of this text on his or her bookshelf. Chapter 1 is the least effective part of the book. Some of the quantum number notation is incorrect (m rather than ml , s rather than ms), some of the language is imprecise, and there are a few clear-cut errors. There is a nice discussion comparing the rmax of 2s and 2p vs 3s and 3p orbitals. However, most readers would be better served by the treatments in advanced inorganic texts such as those by Shriver or Huheey. Chapter 2 addresses vertical trends in the main-group elements. After discussing the influence of atomic size on atomic properties, Mingos describes and explains the second-row anomalies and the reversals in trends resulting from the addition of 3d and 4f subshells. He goes on to account for a variety of trends in the physical and chemical properties of main-group elements and their compounds. The chapter ends with tables summarizing a wide variety of properties, providing a wealth of information I have not seen presented in such a compact format anywhere else. Chapter 3 addresses the horizontal trends and diagonal relationships of the main-group elements. Among the highlights are discussions of the role of exchange energies in determining ionization energies, explanations of the trends in metallic-nonmetallic and ionic-covalent behavior, and comparisons of the elements in groups N and N + 10 (e.g., 3 and 13). Chapter 4 (isoelectronic and isostoichiometric relationships) is for the most part a discussion of bonding and structure. For the chemical educator this may be the most valuable part of the book. There are particularly lucid discussions of Lewis/valence bond descriptions of "hypervalent" molecules that avoid the use of d orbitals. The comparison of multicentered bonding schemes for hypervalent and electron-deficient molecules is also very nice. And not surprisingly, in view of the author's background, the discussion of catenated and cluster molecules is excellent. The final chapter applies the principles introduced in Chapters 2-4 to the d-block and f-block elements. There is a nice discussion of the differences between the properties and trends of the main group elements and the transition metals. Other topics that I think are particularly well treated include the role of compact (n - 1)d and (n - 2)f orbitals; multiple bonding; the EAN rule as a unifying theme (and when not to apply the rule); cluster compounds and isolobal fragments. The chapter concludes with a discussion of the lanthanides, actinides, and the transactinides through element 109. In the preface Mingos states that the book is intended for first- and second-year graduate students. I wholeheartedly agree, although these students may not be sophisticated enough to spot some of the errors in the text and tables. The presentation is probably too condensed for undergraduates. However, there is an abundance of material that should be of value to instructors of inorganic chemistry, particularly at the junior-senior level. In reviewing this book I picked up lots of ideas that will be incorporated into my advanced inorganic chemistry course this fall. If you love inorganic chemistry and enjoy the challenge of helping students understand the principles that bring coherence to this branch of our discipline, you will find Mingos' book to be an invaluable resource.