The observation of the vibrational spectra of adsorbed species provides one of the most incisive methods for und erst an ding chemical and physical phenomena on surfaces. At the present time, many approaches may be applied to studies of molecular vibrations on surfaces. Some of these are used on high-area solids of technological importance (e.g., heterogeneous catalysts) while others are applied to single-crystal substrates to gain better understanding under conditions of controlled surface structure. This book has attempted to bring together in one place a discussion of the major methods used to measure vibrational spectra of surface species. The emphasis is on basic concepts and experimental methods rather than a current survey of the extensive literature in this field. Two introductory chapters describe the basic theoretical aspects of vibrational spectroscopy on surfaces, dealing with normal modes and excitation mechanisms in vibrational spectroscopy. The remaining seven chapters deal with various methods employed to observe surface vibra tions. These are arranged in an order that first treats the use of various methods on surfaces that are not of the single-crystal type. It is in this area that the field first got started in the late 1940s with pioneering work by Terenin and others in the Soviet Union, and by Eisehens and others in the United States in the 1950s. The last four chapters deal with relatively recent methods that permit vibrational studies to be made on single crystal substrates.

Over the past few years, there has been a growing awareness of the vibratio nal properties of solid surfaces and adsorbates due to a steady growth in the number of experimental techniques which have evolved with sufficient resolution and surface sensitivity. An understanding of the surface vibratio nal modes is of fundamental importance in many areas of the physics and chemistry of surfaces, most notably in the field of heterogeneous catalysis on metals and alloys. The present volume derives from a one day meeting of invited lectures, held under the auspices of the Thin Films and Surfaces Section of the Insti tute of Physics in the Cavendish Laboratory, University of Cambridge, 13 December 1979. The object was to bring together specialists from various diverse fields who would examine the wide variety of methods currently avail able for studying surface adsorbate vibrations. Since these methods cover several scientific disciplines, it was subsequently felt that it would be useful to provide a permanent record of the talks as a source lor future reference by workers in what is rapidly becoming an expanding field of',inter est in an increasing number of laboratories. The contributions, however, are not in any way meant to constitute exhaustive reviews.

The book is a multi-author survey (in 15 chapters) of the current state of knowledge and recent developments in our understanding of oxide surfaces. The author list includes most of the acknowledged world experts in this field. The material covered includes fundamental theory and experimental studies of the geometrical, vibrational and electronic structure of such surfaces, but with a special emphasis on the chemical properties and associated reactivity. The main focus is on metal oxides but coverage extends from 'simple' rocksalt materials such as MgO through to complex transition metal oxides with different valencies.

As in the study of transition metal complexes in solution, molecular spectroscopic methods - principally the infrared, ultraviolet/visible and electron spin resonance spectroscopies - have played key roles in establishing the concepts of coordination chemistry occurring at the surfaces of solids. This book describes the development of the principals of coordination chemistry of oxide surfaces using analyses of data obtained by these methods. The nature, properties, concentration of the surface adsorption centers and their influence on the character of interaction with different molecules are investigated. The book commences with an account of the basic theoretical principles and experimental techniques of the various spectroscopy methods, with special attention devoted to in situ measurements where the oxide or catalyst sample is in contact with the adsorbate or the reactant. A detailed account is presented of the methods for characterizing the oxidation state and degree of coordination of surface cations and oxygen anions by the adsorption of probe molecules. The complexation of many inorganic, organometallic and organic molecules with different oxide systems is critically examined, and a classification of formed surface compounds, based on the interaction with definite type of adsorption centers, is given. Possible mechanisms of numerous catalytic reactions, including the transformation of organic molecules over acidic catalysts via the carboionic mechanism, are discussed using the spectroscopic identifications of reaction intermediates. A comprehensive analysis of the literature on the interpretation of the spectra of surface compounds on oxides is presented. This highly illustrated and extensively referenced volume is intended for specialists working in the fields of surface physical chemistry, surface and materials sciences, and adsorption phenomena and is essential reading for those involved in the heterogeneous catalysis by transition metal-oxides.

The Symposium was held to honour the memory of the late Dr. A.J. Tench who made numerous important contributions to our knowledge of the structure, reactivity and adsorption properties of oxide surfaces. This volume contains an up-to-date picture of adsorption and catalysis on oxide surfaces, not in the form of a comprehensive review but in its living aspects of work in progress. It describes detailed studies on the determination of the coordination surface ions, particularly oxide ions, by photoluminescence and reflectance spectroscopy, on the identification of adsorbed species by magnetic optical or surface techniques and on catalysis, with emphasis on new concepts such as catalysis involving excited states or structure sensitive reactions.Professionals working in the industrial and academic laboratories will find the book particularly useful as it provides a state-of-the-art account of our understanding of the structure and adsorption characteristics of oxide surfaces. Contained in the book are first class research papers by leading exponents in this field. A very important issue is that the book highlights for the first time the importance of excited states and structure sensitivity in determining the behaviour of oxide surfaces.