"Imagination and shrewd guesswork are powerful instruments for acquiring scientific knowledge . . . " 1. H. van't Hoff The last decades have witnessed a rapid growth of quantum chemistry and a tremendous increase in the number of very accurate ab initio calculations of the electronic structure of molecules yielding results of admirable accuracy. This dramatic progress has opened a new stage in the quantum mechanical description of matter at the molecular level. In the first place, highly accurate results provide severe tests of the quantum mecha nics. Secondly, modern quantitative computational ab initio methods can be synergetically combined with various experimen tal techniques thus enabling precise numerical characterization of molecular properties better than ever anticipated earlier. However, the role of theory is not exhausted in disclosing the fundamental laws of Nature and production of ever increasing sets of data of high accuracy. It has to provide additionally a means of systematization, recognition of regularities, and ratio nalization of the myriads of established facts avoiding in this way complete chaos. Additional problems are represented by molecular wavefunctions provided by the modern high-level computational quantum chemistry methods. They involve, in principle, all the information on molecular system, but they are so immensely complex that can not be immediately understood in simple and physically meaningful terms. Both of these aspects, categorization and interpretation, call for conceptual models which should be preferably pictorial, transparent, intuitively appealing and well-founded, being sometimes useful for semi quantitative purposes.

This book distills the knowledge gained from research into atoms in molecules over the last 10 years into a unique, handy reference. Throughout, the authors address a wide audience, such that this volume may equally be used as a textbook without compromising its research-oriented character. Clearly structured, the text begins with advances in theory before moving on to theoretical studies of chemical bonding and reactivity. There follow separate sections on solid state and surfaces as well as experimental electron densities, before finishing with applications in biological sciences and drug-design. The result is a must-have for physicochemists, chemists, physicists, spectroscopists and materials scientists.

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 intended for physicists and chemists who need to understand the theory of atomic and molecular structure and processes, and who wish to apply the theory to practical problems. As far as practicable, the book provides a self-contained account of the theory of relativistic atomic and molecular structure, based on the accepted formalism of bound-state Quantum Electrodynamics. The author was elected a Fellow of the Royal Society of London in 1992.

At the close of the nineteenth century and the beginning of the twentieth, our knowledge of the activities in the interior of matter experienced a development which surpassed the boldest hopes that could have been entertained by the chemists and physicists of the nineteenth century. The smallest particles of chemistry, the atoms of the elements, which hitherto had been approached merely by inductive thought, now became tangible realities, so to speak, which could be counted and whose tracks could be photographed. A series of remarkable experimental investigations, stimulated largely by the English physicist, J. J. Thomson, had disclosed the existence of negatively charged particles, the so-called electrons, ⁴/₂₀₀₀ the mass of the smallest atom of the known elements. A theory of electrons, based on Maxwell’s classical electrodynamical theory and developed mainly through the labours of Lorentz in Holland and Larmor in England, had brought the problem of atomic structure into close connection with the theory of radiation. The experiments of Rutherford proved, beyond a doubt, that atoms were composed simply of light, negative electric particles, and small heavy, positive electric particles. The new “quantum theory” of Planck was proving itself very powerful in overcoming grave difficulties in the theory of radiation. The time thus seemed ripe for a comprehensive investigation of the fundamental problem of physics—the constitution of matter, and an explanation in terms of simple general laws of the physical and chemical properties of the atoms of the elements. During the first ten years of the new century the problem was attacked with great zeal by many scientists, and many interesting atomic models were developed and studied. But most of these had more significance for chemistry than for physics, and it was not until 1913 that the work of the Danish physicist, Niels Bohr, paved the way for a really physical investigation of the problem in a remarkable series of papers on the spectrum and atomic structure of hydrogen. The ideas of Bohr, founded as they were on the quantum theory, were startling and revolutionary, but their immense success in explaining the facts of experience after a time won for them the wide recognition of the scientific world, and stimulated work by other investigators along similar lines. The past decade has witnessed an enormous development at the hands of scientists in all parts of the world of Bohr’s original conceptions; but through it all Bohr has remained the leading spirit, and the theory which, at the present time, gives the most comprehensive view of atomic structure may, therefore, most properly bear the name of Bohr. It is the object of this book to give the reader a glimpse of the fundamental conceptions of this theory, together with some of the most significant results it has attained. The book is designed to meet the needs of those who wish to keep abreast of modern developments in science, but have neither time nor inclination to delve into the highly mathematical abstract literature in which the developments are usually concealed. It is with this in mind that the first four chapters have been devoted to a general survey of those parts of physics and chemistry which have close connection with atomic theory. No attempt has been made at a mathematical development, and the physical meaning of such mathematical formulæ as do occur has been clearly emphasized in the text. It is hoped, however, that even those readers whose acquaintance with atomic theory is more than casual, will find the book a stimulus to further study of the Bohr theory. Here we wish to record our best thanks to Mr. and Mrs. Lindsay for the ability and the great care with which they have carried out the translation from the Danish original...FROM THE BOOKS

Relativistic effects are of major importance for understan- ding the properties of heavier atoms and molecules. This book is still the only comprehensive bibliography on related calculations. The material is organized by subject into ta- bles containing a concise characterization. Together with Volume I (Lecture Notes in Chemistry Vol. 41, ISBN 3-540-17167-3) the literature until 1992 is now covered and 6577 references, with titles, are given in the two books. The book will provide aconvenient reference for theoretical chemists and atomic and molecular physicists interested in the properties of heavier elements. Contents: Introduction - One-particle problems - Quantum electrodynamical effects - Multielectron atoms: methods - Multielectron atoms: results - Symmetry - Molecular calcula- tions - Solid-state theory - Relativistic effects and heavy- element chemistry - Corrections to Volume I - Some comments on notations and terminology - List of acronyms and symbols - Bibliography.

This profusely illustrated book, by a world-renowned chemist and award-winning chemistry teacher, provides science students with an introduction to atomic and molecular structure and bonding. (This is a reprint of a book first published by Benjamin/Cummings, 1973.)

Advances in Quantum Chemistry

Relativistic effects are of major importance for understanding the properties of heavier atoms and molecules. Volumes I-III of Relativistic Theory of Atoms and Molecules constitute the only available bibliography on related calculations. In Volume III, 3792 new references covering 1993-1999 are added to the database. The material is characterized by an analysis of the respective papers. The volume gives the user a comprehensive bibliography on relativistic atomic and molecular calculations, including studies on the Dirac equation and related solid-state work.

''A clear and comprehensive introduction to contemporary philosophy of science.'' -- American Scientist ''The best account of scientific theory now available, one that surely commends itself to every philosopher of science with the slightest interest in metaphysics.'' -- Review of Mathematics ''It should certainly be of interest to those teaching graduate courses in philosophy of science and to scientists wishing to gain a further appreciation of the approach used by philosophers of science.'' -- Science Activities