It is widely recognized that an understanding of the physical and chemical properties of clusters will give a great deal of important information relevant to surface and bulk properties of condensed matter. This relevance of clusters for condensed matter is one of the major motivations for the study of atomic and molecular clusters. The changes of properties with cluster size, from small clusters containing only a few atoms to large clusters containing tens of thousands of atoms, provides a unique way to understand and to control the development of bulk properties as separated units are brought together to form an extended system. Another important use of clusters is as theoretical models of surfaces and bulk materials. The electronic wavefunctions for these cluster models have special advantages for understanding, in particular, the local properties of condensed matter. The cluster wavefunctions, obtained with molecular orbital theory, make it possible to relate chemical concepts developed to describe chemical bonds in molecules to the very closely related chemical bonding at the surface and in the bulk of condensed matter. The applications of clusters to phenomena in condensed matter is a cross-disciplinary activity which requires the interaction and collaboration of researchers in traditionally separate areas. For example, it is necessary to bring together workers whose background and expertise is molecular chemistry with those whose background is solid state physics. It is also necessary to bring together experimentalists and theoreticians.

Heterogeneous catalysis provides the backbone of the world's chemical and oil industries. The innate complexity of practical catalytic systems suggests that useful progress should be achievable by investigating key aspects of catalysis by experimental studies on idealised model systems. Thin films and supported clusters are two promising types of model system that can be used for this purpose, since they mimic important aspects of the properties of practical dispersed catalysts. Similarly, appropriate theoretical studies of chemisorption and surface reaction clusters or extended slab systems can provide valuable information on the factors that underlie bonding and catalytic activity. This volume describes such experimental and theoretical approaches to the surface chemistry and catalytic behaviour of metals, metal oxides and metal/metal oxide systems. An introduction to the principles and main themes of heterogeneous catalysis is followed by detailed accounts of the application of modern experimental and theoretical techniques to fundamental problems. The application of advanced experimental methods is complemented by a full description of theoretical procedures, including Hartree-Fock, density functional and similar techniques. The relative merits of the various approaches are considered and directions for future progress are indicated.

On Friday, February 20, 1980, I had the pleasure to be present at the inaugural lecture of my colleague Jan Reedijk, who had just been named at the Chair of Inorganic Chemistry of Leiden University. According to tradition, the ceremony took place in the impressive Hall of the old University Academy Building. In the course of his lecture, Jan mentioned a number of recent developments in chemistry which had struck him as particularly important or interesting. Among those was the synthesis of large metal cluster compounds, and, to my luck, he showed a slide ofthe molecular structure of [PtI9(C)b]4-. (To my luck, since at traditional Leiden University it is quite unusual to show slides at such ceremonies.) This constituted my first acquaintance with this exciting new class of materials. I became immediately fascinated by this molecule, partly because of the esthetic beauty of its fivefold symmetry, partly because as a physicist it struck me that it could be visualized as an "embryonically small" metal particle, embedded in a shell of CO ligands.

Quantum Systems in Chemistry and Physics contains a refereed selection of the papers presented at the first European Workshop on this subject, held at San Miniato, near Pisa, Italy, in April 1996. The Workshop brought together leading experts in theoretical chemistry and molecular physics with an interest in the quantum mechanical many-body problem. This volume provides an insight into the latest research in this increasingly important field. Throughout the Workshop, the emphasis was on innovative theory and conceptual developments rather than on computational implementation. The various contributions presented reflect this emphasis and embrace topics such as density matrices and density functional theory, relativistic formulations, electron correlation, valence theory, nuclear motion, response theory, condensed matter, and chemical reactions. Audience: The volume will be of interest to those working in the molecular sciences and to theoretical chemists and molecular physicists in particular.

In eight volumes, Surface and Interface Science covers all fundamental aspects and offers a comprehensive overview of this research area for scientists working in the field, as well as an introduction for newcomers. Volume 5: Solid-Gas Interfaces I Topics covered: Basics of Adsorption and Desorption Surface Microcalorimetry Adsorption of Rare Gases Adsorption of Alkali and Other Electro-Positive Metals Halogen adsorption on metals Adsorption of Hydrogen Adsorption of Water Adsorption of (Small) Molecules on Metal Surfaces Surface Science Approach to Catalysis Adsorption, Bonding and Reactivity of Unsaturated and Multifunctional Molecules Volume 6: Solid-Gas Interfaces II Topics covered: Adsorption of Large Organic Molecules Chirality of Adsorbates Adsorption on Semiconductor Surfaces Adsorption on Oxide Surfaces Oscillatory Surface Reactions Statistical Surface Thermodynamics Theory of the Dynamics at Surfaces Atomic and Molecular Manipulation

Due to the interaction with the contact medium, the properties of clusters may change or even disappear. Thus the physics of cluster-on-surface systems -- the main subject of this book -- is of fundamental importance. The book addresses a wide audience, from the newcomer to the expert. Starting from fundamental concepts of adsorbate-surface interactions, the modification of electronic properties through electron confinement, and concepts of cluster production, it elucidates the distinct properties of the new metallic nanostructures.