Science advances by leaps and bounds rather than linearly in time. I t is not uncommon for a new concept or approach to generate a lot of initial interest, only to enter a quiet period of years or decades and then suddenly reemerge as the focus of new exciting investigations. This is certainly the case of the reduced density matrices (a k a N-matrices or RDMs), whose promise of a great simplification of quantum-chemical approaches faded away when the prospects of formulating the auxil iary yet essential N-representability conditions turned quite bleak. How ever, even during the period that followed this initial disappointment, the 2-matrices and their one-particle counterparts have been ubiquitous in the formalisms of modern electronic structure theory, entering the correlated-level expressions for the first-order response properties, giv ing rise to natural spinorbitals employed in the configuration interaction method and in rigorous analysis of electronic wavefunctions, and al lowing direct calculations of ionization potentials through the extended Koopmans'theorem. The recent research of Nakatsuji, Valdemoro, and Mazziotti her alds a renaissance of the concept of RDlvls that promotes them from the role of interpretive tools and auxiliary quantities to that of central variables of new electron correlation formalisms. Thanks to the economy of information offered by RDMs, these formalisms surpass the conven tional approaches in conciseness and elegance of formulation. As such, they hold the promise of opening an entirely new chapter of quantum chemistry.

Electron Density and Bonding in Crystals: Principles, Theory and X-Ray Diffraction Experiments in Solid State Physics and Chemistry provides a comprehensive, unified account of the use of diffraction techniques to determine the distribution of electrons in crystals. The book discusses theoretical and practical techniques, the application of electron density studies to chemical bonding, and the determination of the physical properties of condensed matter. The book features the authors' own key contributions to the subject as well a thorough, critical summary of the extensive literature on electron density and bonding. Logically organized, coverage ranges from the theoretical and experimental basis of electron density determination to its impact on investigations of the nature of the chemical bond and its uses in determining electromagnetic and optical properties of crystals. The main text is supplemented by appendices that provide clear, concise guidance on aspects such as systems of units, quantum theory of atomic vibrations, atomic orbitals, and creation and annihilation operators. The result is a valuable compendium of modern knowledge on electron density distributions, making this reference a standard for crystallographers, condensed matter physicists, theoretical chemists, and materials scientists.

This important book collects together stateOCoofOCotheOCoart reviews of diverse topics covering almost all the major areas of modern quantum chemistry. The current focus in the discipline of chemistry OCo synthesis, structure, reactivity and dynamics OCo is mainly on control . A variety of essential computational tools at the disposal of chemists have emerged from recent studies in quantum chemistry. The acceptance and application of these tools in the interfacial disciplines of the life and physical sciences continue to grow. The new era of modern quantum chemistry throws up promising potentialities for further research. Reviews of Modern Quantum Chemistry is a joint endeavor, in which renowned scientists from leading universities and research laboratories spanning 22 countries present 59 inOCodepth reviews. Along with a personal introduction written by Professor Walter Kohn, Nobel laureate (Chemistry, 1998), the articles celebrate the scientific contributions of Professor Robert G Parr on the occasion of his 80th birthday. List of Contributors: W Kohn, M Levy, R Pariser, B R Judd, E Lo, B N Plakhutin, A Savin, P Politzer, P Lane, J S Murray, A J Thakkar, S R Gadre, R F Nalewajski, K Jug, M Randic, G Del Re, U Kaldor, E Eliav, A Landau, M Ehara, M Ishida, K Toyota, H Nakatsuji, G Maroulis, A M Mebel, S Mahapatra, R CarbOCoDorca, u Nagy, I A Howard, N H March, SOCoB Liu, R G Pearson, N Watanabe, S TenOCono, S Iwata, Y Udagawa, E Valderrama, X Fradera, I Silanes, J M Ugalde, R J Boyd, E V Ludea, V V Karasiev, L Massa, T Tsuneda, K Hirao, J-M Tao, J P Perdew, O V Gritsenko, M Grning, E J Baerends, F Aparicio, J Garza, A Cedillo, M Galvin, R Vargas, E Engel, A HAck, R N Schmid, R M Dreizler, J Poater, M Sola, M Duran, J Robles, X Fradera, P K Chattaraj, A Poddar, B Maiti, A Cedillo, S Guti(r)rrezOCoOliva, P Jaque, A ToroOCoLabb(r), H Chermette, P Boulet, S Portmann, P Fuentealba, R Contreras, P Geerlings, F De Proft, R Balawender, D P Chong, A Vela, G Merino, F Kootstra, P L de Boeij, R van Leeuwen, J G Snijders, N T Maitra, K Burke, H Appel, E K U Gross, M K Harbola, H F Hameka, C A Daul, I Ciofini, A Bencini, S K Ghosh, A Tachibana, J M CabreraOCoTrujillo, F Tenorio, O Mayorga, M Cases, V Kumar, Y Kawazoe, A M KAster, P Calaminici, Z Gmez, U Reveles, J A Alonso, L M Molina, M J Lpez, F Dugue, A Maanes, C A Fahlstrom, J A Nichols, D A Dixon, P A Derosa, A G Zacarias, J M Seminario, D G Kanhere, A Vichare, S A Blundell, ZOCoY Lu, HOCoY Liu, M Elstner, WOCoT Yang, J Muoz, X Fradera, M Orozco, F J Luque, P Tarakeshwar, H M Lee, K S Kim, M Valiev, E J Bylaska, A Gramada, J H Weare, J Brickmann, M Keil, T E Exner, M Hoffmann & J Rychlewski. Contents: Volume I: Applications of the Automorphisms of SO(8) to the Atomic f Shell (B R Judd & E Lo); Probability Distributions and Valence Shells in Atoms (A Savin); Information Theoretical Approaches to Quantum Chemistry (S R Gadre); Quantum Chemical Justification for Clar''s Valence Structures (M Randic); Functional Expansion Approach in Density Functional Theory (S-B Liu); Normconserving Pseudopotentials for the Exact Exchange Functional (E Engel et al.); Volume II: Chemical Reactivity and Dynamics within a Density-based Quantum Mechanical Framework (P K Chattaraj et al.); Fukui Functions and Local Softness (H Chermette et al.); The Nuclear Fukui Function (P Geerlings et al.); Causality in Time-Dependent Density-Functional Theory (M K Harbola); Theoretical Studies of Molecular Magnetism (H F Hameka); Melting in Finite-Sized Systems (D G Kanhere et al.); Density Functional Theory (DFT) and Drug Design (M Hoffmann & J Rychlewski); and other papers. Readership: Researchers and academics in computational, physical, fullerene, industrial, polymer, solid state and theoretical/quantum chemistry; nanoscience, superconductivity & magnetic materials, surface science; atomic, computational and condensed matter physics; and thermodynamics."

The first edition of "The Stability of Matter: From Atoms to Stars" was sold out after a time unusually short for a selecta collection and we thought it ap propriate not just to make a reprinting but to include eight new contributionso They demonstrate that this field is still lively and keeps revealing unexpected featureso Of course, we restricted ourselves to developments in which Elliott Lieb participated and thus the heroic struggle in Thomas-Fermi theory where 7 3 5 3 the accuracy has been pushed from Z 1 to Z 1 is not includedo A rich landscape opened up after Jakob Yngvason's observation that atoms in magnetic fields also are described in suitable limits by a Thomas-Fermi-type theoryo Together with Elliott Lieb and Jan Philip Solovej it was eventually worked out that one has to distinguish 5 regionso If one takes as a dimensionless measure of the magnetic field strength B the ratio Larmor radius/Bohr radius one can compare it with N "' Z and for each of the domains 4 3 (i) B « N 1 , 4 3 (ii) B "' N 1 , 4 3 3 (iii) N 1« B « N , 3 (iv) B "' N , 3 (v) B » N a different version ofmagnetic Thomas-Fermi theory becomes exact in the limit N --+ ooo In two dimensions and a confining potential ("quantum dots") the situation is somewhat simpler, one has to distinguish only (i) B « N, (ii) B "'N,

Focusing on developments from the past 10-15 years, this volume presents an objective overview of the research in charge density analysis. The most promising methodologies are included, in addition to powerful interpretative tools and a survey of important areas of research.

This book is a rigorous, unified account of the fundamental principles of the density-functional theory of the electronic structure of matter and its applications to atoms and molecules. Containing a detailed discussion of the chemical potential and its derivatives, it provides an understanding of the concepts of electronegativity, hardness and softness, and chemical reactivity. Both the Hohenberg-Kohn-Sham and the Levy-Lieb derivations of the basic theorems are presented, and extensive references to the literature are included. Two introductory chapters and several appendices provide all the background material necessary beyond a knowledge of elementary quantum theory. The book is intended for physicists, chemists, and advanced students in chemistry.

This book is an outcome of the International Workshop on Electronic Density Functional Theory, held at Griffith University in Brisbane, Australia, in July 1996. Density functional theory, standing as it does at the boundary between the disciplines of physics, chemistry, and materials science, is a great mixer. Invited experts from North America, Europe, and Australia mingled with students from several disciplines, rapidly taking up the informal style for which Australia is famous. A list of participants is given at the end of the book. Density functional theory (DFT) is a subtle approach to the very difficult problem of predicting the behavior of many interacting particles. A major application is the study of many-electron systems. This was the workshop theme, embracing inter alia computational chemistry and condensed matter physics. DFT circumvents the more conceptually straightforward (but more computationally intensive) approach in which one solves the many-body Schrodinger equation. It relies instead on rather delicate considerations involving the electron number density. For many years the pioneering work of Kohn and Sham (the Local Density Ap proximation of 1965 and immediate extensions) represented the state of the art in DFT. This approach was widely used for its appealing simplicity and computability, but gave rather modest accuracy. In the last few years there has been a renaissance of interest, quite largely due to the remarkable success of the new generation of gradient functionals whose initiators include invitees to the workshop (Perdew, Parr, Yang).

Valence Shell Electron Pair Repulsion (VSEPR) theory is a simple technique for predicting the geometry of atomic centers in small molecules and molecular ions. This authoritative reference was written by Istvan Hartiggai and the developer of VSEPR theory, Ronald J. Gillespie. In addition to its value as a text for courses in molecular geometry and chemistry, it constitutes a classic reference for professionals. Starting with coverage of the broader aspects of VSEPR, this volume narrows its focus to a succinct survey of the methods of structural determination. Additional topics include the applications of the VSEPR model and its theoretical basis. Helpful data on molecular geometries, bond lengths, and bond angles appear in tables and other graphics.