One of the major developments in Earth Sciences in general, and mineralogy in particular, has been the growth of our understanding of the microscopic behaviour of the complex materials that make up the Earth. This has been made possible by advances in our ability to probe minerals at the atomic level, over a large range of pressure and temperature conditions. New experimental techniques include the use of scanning probe microscopies to investigate mineral surfaces, as well as the use of neutron scattering, nuclear spectroscopies and synchrotron radiation to investigate the bonding and structure of minerals. In addition, there have been major developments in computational methods so that it is now possible to calculate the electronic structure of many rock forming materials. The aim of this volume is to give a coherent survey of the latest developments in experimental and theoretical approaches to the study of microscopic propertie~ and processes in minerals. Chapters in the book cover a number of key themes in the mineral sciences such as the behaviour of minerals at extremes of pressure and temperature, ordering in complex silicates, mechanisms of water incorporation in mantle phases, the importance of reactions occurring at the mineral surface, and the ability of computational methods to provide useful, qualitative information on the bulk and surface properties of minerals. The background to several experimental techniques is covered in some detail with examples of relevance to the issues cited above.

Computer Modelling techniques have developed very rapidly during the last decade, and interact with many contemporary scientific disciplines. One of the areas of greatest activity has concerned the modelling of condensed phases, including liquids solids and amorphous systems, where simulations have been used to provide insight into basic physical processes and in more recent years to make reliable predictions of the properties of the systems simulated. Indeed the predictive role of simulations is increasingly recognised both in academic and industrial contexts. Current active areas of application include topics as diverse as the viscosity of liquids, the conformation of proteins, the behaviour of hydrogen in metals, the diffusion of molecules in porous catalysts and the properties of micelles. This book, which is based on a NATO ASI held at the University of Bath, UK, from September 5th-17th, 1988, aims to give a general survey of this field, with detailed discussions both of methodologies and of applications. The earlier chapters of the book are devoted mainly to techniques and the later ones to recent simulation studies of fluids, polymers (including biological molecules) and solids. Special attention is paid to the role of interatomic potentials which are the fundamental physical input to simulations. In addition, developments in computer hardware are considered in depth, owing to the crucial role which such developments are playing in the expansion of the horizons of computer modelling studies.

Materials chemistry is a growing interdisciplinary field which interfaces with and draws from many disciplines including solid state chemistry and physics, materials science and crystallography. This volume provides a review of the main techniques and topical materials presented by leading workers in the field. The survey of techniques includes in-depth coverage of diffraction, microscopy, NMR and IR spectroscopic methods; and special emphasis is given to the growing role of computational and theoretical techniques. The development of new materials with specific applications is a major feature of contemporary materials chemistry. Later chapters of the book emphasize ionic conductors, superconductors, colossal magneto-resistance materials and catalytic systems (including micro- and meso-porous materials), to which several chapters are devoted. Synthetic aspects of the field are also emphasized. This comprehensive survey of the field should be of interest to research workers in the area of materials chemistry or related disciplines. It should also serve as an introduction to the field for graduate students.

The study of disorder in solids is one of the key areas in contemporary solid state science. In crystalline solids there are well-developed models for describing the way in which defects control the atomic transport, thermodynamic and spectroscopic properties. In contrast, the conceptual and theoretical framework for describing these properties in amorphous solids is less well developed, partly due to the uncertainties in the structural models used to represent the disordered systems. Moreover, disordered solids include materials of great contemporary technological importance, for example, ceramic superconductors and amorphous semiconductors. The field has developed rapidly in the last few years, driven both by technological needs for improved materials and by the fundamental scientific problems posed by disorder in solids. Progress has been especially rapid in structural studies, using diffraction, EXAFS, NMR and microscopy techniques, in investigation of atomic and charge transport and in the application of theoretical and computational methods. The book provides a unified approach to disorder in solids. The earlier chapters present a survey of the theoretical and structural concepts used in describing defective and amorphous solids and the basic properties of these materials. The next chapters are devoted to a thorough survey of techniques and properties, including structural studies, transport, thermodynamic and spectroscopic properties and theoretical and computational techniques. The final chapters review materials and applications, including fast-ion conductors, sensors, amorphous semiconductors and novel glasses. It therefore presents a unique survey of an important field incontemporary solid state science.

The study of defects and disorder in solids remains a central topic in solid state science. Developments in the field continue to be promoted by new experimental and theoretical techniques, while further impetus for the study of disorder in solids is provided by the growing range of applications of solid state materials in which disorder at the atomic level plays a crucial rOle. In this book we attempt to present a survey of fundamental and applied aspects of the field. We consider the basic aspects of defective crystalline and amorphous solids. We discuss recent studies of structural, electronic, transport, thermodynamic and spectroscopic properties of such materials. Experimental and theoretical methodologies are reviewed, and detailed consideration is given to materials such as fast ion conductors and amorphous semiconductors that are of importance in an applied context. Any survey of this large field is necessarily selective. We have chosen to emphasise insulating (especially oxidic) and semi-conducting materials. But many of the approaches and techniques we describe apply generally across the entire field of solid state science. This volume is based on a NATO ASI held at the Residencia Santa Teresa de Jesus, Madrid in September 1991. The Editor is grateful to the NATO Scientific Affairs Division for their sponsorship of this School. Thanks are also due to all who participated in and lectured at the school, but especially to the organising committee of A. V. Chadwick, G. N. Greaves, M. Grigorkiewicz, J. H. Harding and S. Kalbitzer. C. R. A.

Materials Chemistry is rapidly emerging as a key component of contemporary science. The strongly interdisciplinary nature of the field requires input from all branches of chemistry, from crystallography, from solid state physics and from computational and theoretical techniques. This book aims to give a coherent survey of the field by considering all the major aspects of the current study of the chemistry of materials. Early chapters emphasise basic principles and techniques. Strong emphasis is given to new techniques and technologies, for example, the opportunities opened up by new synchrotron sources in crystallography, and new computational techniques in simulation studies of complex materials. Characterisation techniques including crystallographic, microscopic and spectroscopic techniques are then described. Key contemporary themes such as atomic transport, reactivity and catalysis are reviewed. Later chapters focus on specific dasses of material, induding solid state ionics, ceramics (induding giant magneto-resistance and high temperature superconducting solids), microporous and molecular materials. We hope that the book provides a snapshot of the scientific and technological challenges in this fast developing field. The editors would like to thank the NATO Scientific Affairs Division for funding the School on which this volume is basedj financial contribution from Johnson Matthey Technology Centre is also gratefully acknowledged. We are most grateful to Mrs Jean Conisbee for all her efforts in preparing the manuscript.

Computer Modelling techniques have developed very rapidly during the last decade, and interact with many contemporary scientific disciplines. One of the areas of greatest activity has concerned the modelling of condensed phases, including liquids solids and amorphous systems, where simulations have been used to provide insight into basic physical processes and in more recent years to make reliable predictions of the properties of the systems simulated. Indeed the predictive role of simulations is increasingly recognised both in academic and industrial contexts. Current active areas of application include topics as diverse as the viscosity of liquids, the conformation of proteins, the behaviour of hydrogen in metals, the diffusion of molecules in porous catalysts and the properties of micelles. This book, which is based on a NATO ASI held at the University of Bath, UK, from September 5th-17th, 1988, aims to give a general survey of this field, with detailed discussions both of methodologies and of applications. The earlier chapters of the book are devoted mainly to techniques and the later ones to recent simulation studies of fluids, polymers (including biological molecules) and solids. Special attention is paid to the role of interatomic potentials which are the fundamental physical input to simulations. In addition, developments in computer hardware are considered in depth, owing to the crucial role which such developments are playing in the expansion of the horizons of computer modelling studies.

Synchrotron radiation became available in a routine and regular manner to the scientific community in the early 1980s. Since that time the use of techniques employing synchrotron radiation has proliferated, so that the unique properties of this form ofelectromagnetic radiation are now having a major impact on several areas of physical and biological sciences. Not only have several new techniques become available but new opportunities with existing methodologies, e.g. diffraction, have been opened up. In this book we providea surveyofsomeofthemostimportantapplications ofsynchrotron radiation, with astrongemphasison the fields ofchemistry and materials science. An introduction to the properties of the radiation and its instrumentation is given in chapter 1. The following chapters describe the use ofsynchrotron radiation in high resolution powder diffraction for structural studies of crystalline materials and in diffraction topography for imaging defects in single crystals. The role of EXAFS in investigations of amorphous and disordered crystalline solids and ofbiological systems is highlighted. The important enhancements to surface science techniques offered by synchrotron radiation are then reviewed. Later chapters describe more specialist applic ations, including trace-element analysis, protein crystallography, X-ray microscopy, and atomic and molecular spectroscopy."

One of the major developments in Earth Sciences in general, and mineralogy in particular, has been the growth of our understanding of the microscopic behaviour of the complex materials that make up the Earth. This has been made possible by advances in our ability to probe minerals at the atomic level, over a large range of pressure and temperature conditions. New experimental techniques include the use of scanning probe microscopies to investigate mineral surfaces, as well as the use of neutron scattering, nuclear spectroscopies and synchrotron radiation to investigate the bonding and structure of minerals. In addition, there have been major developments in computational methods so that it is now possible to calculate the electronic structure of many rock forming materials. The aim of this volume is to give a coherent survey of the latest developments in experimental and theoretical approaches to the study of microscopic propertie~ and processes in minerals. Chapters in the book cover a number of key themes in the mineral sciences such as the behaviour of minerals at extremes of pressure and temperature, ordering in complex silicates, mechanisms of water incorporation in mantle phases, the importance of reactions occurring at the mineral surface, and the ability of computational methods to provide useful, qualitative information on the bulk and surface properties of minerals. The background to several experimental techniques is covered in some detail with examples of relevance to the issues cited above.