This textbook introduces the molecular and quantum chemistry needed to understand the physical properties of molecules and their chemical bonds. It follows the authors' earlier textbook "The Physics of Atoms and Quanta" and presents both experimental and theoretical fundamentals for students in physics and physical and theoretical chemistry. The new edition treats new developments in areas such as high-resolution two-photon spectroscopy, ultrashort pulse spectroscopy, photoelectron spectroscopy, optical investigation of single molecules in condensed phase, electroluminescence, and light-emitting diodes.

`Quantum Chemistry [the branch of Computational Chemistry that applies the laws of Quantum Mechanics to chemical systems] is one of the most dynamic fields of contemporary chemistry, providing a solid foundation for all of chemistry, and serving as the basis for practical, computational methodologies with applications in virtually all branches of chemistry ... The increased sophistication, accuracy and scope of the theory of chemistry are due to a large extent to the spectacular development of quantum chemistry, and in this book the authors have made a remarkable effort to provide a modern account of the field.' From the Foreword by Paul Mezey, University of Saskatchewan. Quantum Chemistry: Fundamentals to Applications develops quantum chemistry all the way from the fundamentals, found in Part I, through the applications that make up Part II. The applications include: molecular structure; spectroscopy; thermodynamics; chemical reactions; solvent effects; and excited state chemistry. The importance of this field is underscored by the fact that the 1998 Nobel Prize in Chemistry was awarded for the development of Quantum Chemistry.

The richly illustrated book comprehensively explains the important principles of diatomic and polyatomic molecules and their spectra in two separate, distinct parts. The first part concentrates on the theoretical aspects of molecular physics, such as the vibration, rotation, electronic states, potential curves, and spectra of molecules. The different methods of approximation for the calculation of electronic wave functions and their energy are also covered. The introduction of basics terms used in group theory and their meaning in molecular physics enables an elegant description of polyatomic molecules and their symmetries. Molecular spectra and the dynamic processes involved in their excited states are given its own chapter. The theoretical part then concludes with a discussion of the field of Van der Waals molecules and clusters. The second part is devoted entirely to experimental techniques, such as laser, Fourier, NMR, and ESR spectroscopies, used in the fields of physics, chemistry, biology, and material science. Time-resolved measurements and the influence of chemical reactions by coherent controls are also treated. A list of general textbooks and specialized literature is provided for further reading. With specific examples, definitions, and notes integrated within the text to aid understanding, this is suitable for undergraduates and graduates in physics and chemistry with a knowledge of atomic physics and familiar with the basics of quantum mechanics.

Computational chemistry is increasingly used in most areas of molecular science including organic, inorganic, medicinal, biological, physical, and analytical chemistry. Researchers in these fields who do molecular modelling need to understand and stay current with recent developments. This volume, like those prior to it, features chapters by experts in various fields of computational chemistry. Two chapters focus on molecular docking, one of which relates to drug discovery and cheminformatics and the other to proteomics. In addition, this volume contains tutorials on spin-orbit coupling and cellular automata modeling, as well as an extensive bibliography of computational chemistry books. FROM REVIEWS OF THE SERIES "Reviews in Computational Chemistry remains the most valuable reference to methods and techniques in computational chemistry."—JOURNAL OF MOLECULAR GRAPHICS AND MODELLING "One cannot generally do better than to try to find an appropriate article in the highly successful Reviews in Computational Chemistry. The basic philosophy of the editors seems to be to help the authors produce chapters that are complete, accurate, clear, and accessible to experimentalists (in particular) and other nonspecialists (in general)."—JOURNAL OF THE AMERICAN CHEMICAL SOCIETY

The highly positive affirmation and wide reception that this book continues to receive from professors and students ahke is the occasion for this 7th edition. Once again we have included a number of valuable suggestions for improvements, which we address as appropriate. In addition, we refer to a number of developments in atomic physics. Of these new developments in regard to exotic atoms, we mention antihydrogen in par ticular, because fundamental experiments in matter and antimatter can be expected in the future. Furthermore, we have inserted a chapter on the behaviour of atoms in strong elec trical fields. Experiments with corresponding lasers could only recently be realized. We thank our Jenaer colleague, R. Sauerbrey, for his contribution of this chapter. We have also included a new chapter on the behaviour of the hydrogen atom in strong magnetic fields. The results are of profound interest for two very different fields of physics: on the one hand, according to classical physics, one expects chaotic behaviour from Rydberg atoms in magnetic fields that can be created in the laborato ry; thus, an association can be drawn to aspects of chaos theory and the problems of quantum chaos. On the other hand, the very strong fields necessary for low quantum numbers are realized in the cosmos, in particular with white dwarfs and neutron stars.

The Physics of Atoms and Quanta is a thorough introduction to experiments and theory in this field. Every classical and modern aspect is covered and discussed in detail. The sixth edition includes new developments, as well as new experiments in quantum entanglement, Schrodingers cat, the quantum computer, quantum information, the atom laser, and much more. A wealth of experiments and problems are included. As this reference ends with the fundamentals of classical bonding, it leads into the authors' more advanced book Molecular Physics and Elements of Quantum Chemistry.

This book contains the transcripts of the lectures presented at the NATO Advanced study Institute on "Computational Techniques in Quantum Chemistry and Molecular Physics", held at Ramsau, Germany, 4th - 21st Sept. 1974. Quantum theory was developed in the early decades of this century and was first applied to problems in chemistry and molecular physics as early as 1927. It soon emerged however, that it was impossible to con sider any but the simplest systems in any quantita tive detail because of the complexity of Schrodinger's equation which is the basic equation for chemical and molecular physics applications. This remained the si tuation until the development, after 1950, of elec tronic digital computers. It then became possible to attempt approximate solutions of Schrodinger's equa tion for fairly complicated systems, to yield results which were sufficiently accurate to make comparison with experiment meaningful. Starting in the early nineteen sixties in the United States at a few centres with access to good computers an enormous amount of work went into the development and implementation of schemes for approximate solu tions of Schrodinger's equation, particularly the de velopment of the Hartree-Fock self-consistent-field scheme. But it was soon found that the integrals needed for application of the methods to molecular problems are far from trivial to evaluate and cannot be easily approximated.

Quantum mechanics provides the fundamental theoretical apparatus for describing the structure and properties of atoms and molecules in terms of the behaviour of their fundamental components, electrons and nudeL For heavy atoms and molecules containing them, the electrons can move at speeds which represent a substantial fraction of the speed of light, and thus relativity must be taken into account. Relativistic quantum mechanics therefore provides the basic formalism for calculating the properties of heavy-atom systems. The purpose of this book is to provide a detailed description of the application of relativistic quantum mechanics to the many-body prob lem in the theoretical chemistry and physics of heavy and superheavy elements. Recent years have witnessed a continued and growing interest in relativistic quantum chemical methods and the associated computa tional algorithms which facilitate their application. This interest is fu elled by the need to develop robust, yet efficient theoretical approaches, together with efficient algorithms, which can be applied to atoms in the lower part of the Periodic Table and, more particularly, molecules and molecular entities containing such atoms. Such relativistic theories and computational algorithms are an essential ingredient for the description of heavy element chemistry, becoming even more important in the case of superheavy elements. They are destined to become an indispensable tool in the quantum chemist's armoury. Indeed, since relativity influences the structure of every atom in the Periodic Table, relativistic molecular structure methods may replace in many applications the non-relativistic techniques widely used in contemporary research.

Per-Olov Löwdin's stature has been a symbol of the world of quantum theory during the past five decades, through his basic contributions to the development of the conceptual framework of Quantum Chemistry and introduction of the fundamental concepts; through a staggering number of regular summer schools, winter institutes, innumerable lectures at Uppsala, Gainesville and elsewhere, and Sanibel Symposia; by founding the International Journal of Quantum Chemistry and Advances in Quantum Chemistry; and through his vision of the possible and his optimism for the future, which has inspired generations of physicists, chemists, mathematicians, and biologists to devote their lives to molecular electronic theory and dynamics, solid state, and quantum biology. Fundamental World of Quantum Chemistry: Volumes I, II and III form a collection of papers dedicated to the memory of Per-Olov Löwdin. These volumes are of interest to a broad audience of quantum, theoretical, physical, biological, and computational chemists; atomic, molecular, and condensed matter physicists; biophysicists; mathematicians working in many-body theory; and historians and philosophers of natural science.

This volume records the lectures given at a NATO Advanced Study Institute on Methods in Computational Molecular Physics held in Bad Windsheim, Germany, from 22nd July until 2nd. August, 1991. This NATO Advanced Study Institute sought to bridge the quite considerable gap which exist between the presentation of molecular electronic structure theory found in contemporary monographs such as, for example, McWeeny's Methods 0/ Molecular Quantum Mechanics (Academic Press, London, 1989) or Wilson's Electron correlation in moleeules (Clarendon Press, Oxford, 1984) and the realization of the sophisticated computational algorithms required for their practical application. It sought to underline the relation between the electronic structure problem and the study of nuc1ear motion. Software for performing molecular electronic structure calculations is now being applied in an increasingly wide range of fields in both the academic and the commercial sectors. Numerous applications are reported in areas as diverse as catalysis and interstellar chernistry, drug design and environmental studies, molecular biology and solid state physics. The range of applications continues to increase as scientists recognize the importance of molecular structure studies to their research activities. Recent years have seen a growing dependence of these applications on program packages, which are often not in the public domain and which may have a somewhat lirnited range of applicability dicta ted by the particular interests and prejudices of the program author.