This treatise is devoted to an analysis of the present state of the quantum theory of chemical reactions. It will be divided into three volumes and will contain the contributions to an international seminar organized by the editors. The first one, is concerned with the fundamental problems which occur when studying a gas phase reaction or a reaction for which the solvent effect is not taken into account. The two first papers show how the collision theory can be used to predict the behaviour of interacting small molecules. For large molecules the complete calculations are not possible. We can only estimate the reaction path by calculating important areas of the potential surfaces. Four papers are concerned with this important pro cess. Furthermore, in one of these, the electronic reorganization which occurs along the reaction path is carefully analyzed. ~~o papers are devoted to the discussion of general rules as aromaticity rules, symmetry rules. The last two papers are concerned with the electrostatic molecular poten tial method which is the modern way of using static indices to establish relations between structure and chemical reactivity. Volume II will be devoted to a detailed analysis of the role of the solvent and volume III will present important applications as reaction mechanisms, photochemistry, catalysis, biochemical reactions and drug design. SOME RECENT DEVELOPMENTS IN THE MOLECULAR TREATMENT OF ATOM-ATOM COLLISIONS.

Quantum Theory of Chemical Reactivity may be read without reference to the fact that it is actually the third of three volumes of a treatise on quantum chemistry, the science resulting from the implementation of mathematical laws in the realm of molecular populations. The first two volumes of the treatise, 'Fondement de la Chimie Tbeorique' and 'Structure Electrique des Molecules' were, like this third volume, originally published by Gauthier-Villars; Pergamon published the English translations of these two volumes. I am grateful to D. Reidel Publishing Company for translating the third volume of the treatise into English. Readers familiar with English rather than French now have access to the complete series. This treatise is a reflection of the courses I taught at the Sorbonne from 1950 until 1967 to students in their second cycle (3rd and 4th year) and third cycle (5th and 6th year) working towards a doctorate in this particular field. It is based on the reading of over a thousand articles, and is intended for students as well as for physical chemists, and chemists, research workers and engineers taking an interest in quantum chemistry for its own sake or for its application in industry, pharmacology and the life sciences. Reidel's initiative is particularly valuable because in my opinion Quantum Theory of Chemical Reactivity is the most important of the three volumes of the treatise. Doubtless for this reason only the third volume was published in Japanese by Baifukan, thanks to Professors Hayashi and Sohma.

The calculation of cross sections and rate constants for chemical reactions in the gas phase has long been a major problem in theoretical chemistry. The need for reliable and applicable theories in this field is evident when one considers the significant recent advances that have been made in developing experimental techniques, such as lasers and molecular beams, to probe the microscopic details of chemical reactions. For example, it is now becoming possible to measure cross sections for chemical reactions state selected in the vibrational rotational states of both reactants and products. Furthermore, in areas such as atmospheric, combustion and interstellar chemistry, there is an urgent need for reliable reaction rate constant data over a range of temperatures, and this information is often difficult to obtain in experiments. The classical trajectory method can be applied routinely to simple reactions, but this approach neglects important quantum mechanical effects such as tunnelling and resonances. For all these reasons, the quantum theory of reactive scattering is an area that has received considerable attention recently. This book describes the proceedings of a NATO Advanced Research Workshop held at CECAM, Orsay, France in June, 1985. The Workshop concentrated on a critical examination and discussion of the recent developments in the theory of chemical reaction dynamics, with particular emphasis on quantum theories. Several papers focus on exact theories for reactions.

Since the discovery of quantum mechanics,more than fifty years ago,the theory of chemical reactivity has taken the first steps of its development. The knowledge of the electronic structure and the properties of atoms and molecules is the basis for an un derstanding of their interactions in the elementary act of any chemical process. The increasing information in this field during the last decades has stimulated the elaboration of the methods for evaluating the potential energy of the reacting systems as well as the creation of new methods for calculation of reaction probabili ties (or cross sections) and rate constants. An exact solution to these fundamental problems of theoretical chemistry based on quan tum mechanics and statistical physics, however, is still impossible even for the simplest chemical reactions. Therefore,different ap proximations have to be used in order to simplify one or the other side of the problem. At present, the basic approach in the theory of chemical reactivity consists in separating the motions of electrons and nu clei by making use of the Born-Oppenheimer adiabatic approximation to obtain electronic energy as an effective potential for nuclear motion. If the potential energy surface is known, one can calculate, in principle, the reaction probability for any given initial state of the system. The reaction rate is then obtained as an average of the reaction probabilities over all possible initial states of the reacting ~artic1es. In the different stages of this calculational scheme additional approximations are usually introduced.

These two volumes collect thirty-eight selected papers from the scientific contributions presented at the Fourth European Workshop on Quantum Systems in Chemistry and Physics (QSCP-IV), held in Marly-le-Roi (France) in April 22-27, 1999. A total of one hundred and fifteen scientists attended the workshop, 99 from Europe and 16 from the rest of the world. They discussed the state of the art, new trends, and future evolution of the methods and applications. The workshop was held in the old town of Marly-le-Roi, which lies to the West of Paris between the historic centres of Saint-Germain-en-Laye and Versailles. Participants were housed at the National Youth Institute, where over sixty lectures were given by l- ding members of the scientific community; in addition, over sixty posters were presented in two very animated sessions. We are grateful to the oral speakers and to the poster p- senters for making the workshop such an stimulating experience. The social programme was also memorable – and not just for the closing banquet, which was held at the French Senate House. We are sure that participants will long remember their visit to the 'Musée des Antiquités Nationales': created by Napoleon III at the birthplace of Louis XIV, this museum boasts one of the world finest collections of archeological artifacts. The Marly-le-Roi workshop followed the format established at the three previous meetings, organized by Prof.

Advances in Quantum Methods and Applications in Chemistry, Physics, and Biology includes peer-reviewed contributions based on carefully selected presentations given at the 17th International Workshop on Quantum Systems in Chemistry, Physics, and Biology. New trends and state-of-the-art developments in the quantum theory of atomic and molecular systems, and condensed matter (including biological systems and nanostructures) are described by academics of international distinction.

The Encyclopedia of Physical Chemistry and Chemical Physics introduces possibly unfamiliar areas, explains important experimental and computational techniques, and describes modern endeavors. The encyclopedia quickly provides the basics, defines the scope of each subdiscipline, and indicates where to go for a more complete and detailed explanation. Particular attention has been paid to symbols and abbreviations to make this a user-friendly encyclopedia. Care has been taken to ensure that the reading level is suitable for the trained chemist or physicist. The encyclopedia is divided in three major sections: FUNDAMENTALS: the mechanics of atoms and molecules and their interactions, the macroscopic and statistical description of systems at equilibrium, and the basic ways of treating reacting systems. The contributions in this section assume a somewhat less sophisticated audience than the two subsequent sections. At least a portion of each article inevitably covers material that might also be found in a modern, undergraduate physical chemistry text. METHODS: the instrumentation and fundamental theory employed in the major spectroscopic techniques, the experimental means for characterizing materials, the instrumentation and basic theory employed in the study of chemical kinetics, and the computational techniques used to predict the static and dynamic properties of materials. APPLICATIONS: specific topics of current interest and intensive research. For the practicing physicist or chemist, this encyclopedia is the place to start when confronted with a new problem or when the techniques of an unfamiliar area might be exploited. For a graduate student in chemistry or physics, the encyclopedia gives a synopsis of the basics and an overview of the range of activities in which physical principles are applied to chemical problems. It will lead any of these groups to the salient points of a new field as rapidly as possible and gives pointers as to where to read about the topic in more detail.

The fourth volume of the Collected Works is devoted to Wigners contribution to physical chemistry, statistical mechanics and solid-state physics. One corner stone was his introduction of what is now called the Wigner function, while his paper on adiabatic perturbations foreshadowed later work on Berry phases. Although few in number, Wigners articles on solid-state physics laid the foundations for the modern theory of the electronic structure of metals.

This book gathers original contributions from a selected group of distinguished researchers that are actively working in the theory and practical applications of solvent effects and chemical reactions. The importance of getting a good understanding of surrounding media effects on chemical reacting system is difficult to overestimate. Applications go from condensed phase chemistry, biochemical reactions in vitro to biological systems in vivo. Catalysis is a phenomenon produced by a particular system interacting with the reacting subsystem. The result may be an increment of the chemical rate or sometimes a decreased one. At the bottom, catalytic sources can be characterized as a special kind of surrounding medium effect. The materials involving in catalysis may range from inorganic components as in zeolites, homogenous components, enzymes, catalytic antibodies, and ceramic materials. . With the enormous progress achieved by computing technology, an increasing number of models and phenomenological approaches are being used to describe the effects of a given surrounding medium on the electronic properties of selected subsystem. A number of quantum chemical methods and programs, currently applied to calculate in vacuum systems, have been supplemented with a variety of model representations. With the increasing number of methodologies applied to this important field, it is becoming more and more difficult for non-specialist to cope with theoretical developments and extended applications. For this and other reasons, it is was deemed timely to produce a book where methodology and applications were analyzed and reviewed by leading experts in the field.