For several years, core level spectroscopies and other, c\osely related, electron spectroscopies have provided very useful information about the atomic composition, the geometric structure, and the electronic structure of condensed matter. Recently, these spectroscopies have also been used for the study of magnetic properties; such studies have a great potential to extend our knowledge and understanding of magnetic systems. This volume collects the lectures presented at the NATO Advanced Study Institute on "Core Level Spectroscopies for Magnetic Phenomena: Theory and Experiment" held at the Ettore Majorana Centre, Erice, Sicily, on 15 to 26 May 1994. The topics considered at the ASI covered a wide range of subjects involving the use of core-level and related spectroscopies to study magnetic phenomena. There are a large and growing number of applications of these spectroscopies to the study of magnetic materials; an important objective of the ASI was to stimulate further growth. The topics covered at the ASI can be placed into three general groups: 1) fundamental principles of core level spectroscopies; 2) basic aspects of magnetic phenomena; and, 3) the combination of the two previous topics embodied in applications of the spectroscopies to magnetism. In all three groups, theoretical interpretations as weH as experimental measurements were presented, often both of these aspects were covered in a single lecture or series oflectures. The theoretical treatments ofthe spectroscopies as weH as of the magnetic phenomena help to establish a framework for understanding many of the experimental measurements on magnetic materials.

The quantum Hall effect, low-dimensional systems, vortices and superconductivity, high-resolution NMR and EPR spectroscopy - all these and many other landmark contributions of high-magnetic-field physics to solid state science, analytical chemistry and structural biology are presented in this book. Each chapter describes the key concepts and future prospects in the corresponding field. The text can be read at different levels: researchers will find depth and insight, while students will come to understand the basic concepts. This book, written by leading scientists, will serve as a reference work on high-magnetic-field science for many years to come.

Core level spectroscopy has become a powerful tool in the study of electronic states in solids. From fundamental aspects to the most recent developments, Core Level Spectroscopy of Solids presents the theoretical calculations, experimental data, and underlying physics of x-ray photoemission spectroscopy (XPS), x-ray absorption spectroscopy (XAS), x

Among the many tools one has in hand in material science, the various electronic spectroscopies are of particular interest. Techniques based on synchrotron radiation, such as spin-resolved photoemission, X-ray magnetic circular and linear dichroism, resonant X-ray scattering and also X-ray magnetic microscopy have been shown to provide unique tools for the study of the magnetic phenomena and magnetic materials. However, it became apparent that all these new achievements need a strong theoretical support. Ab-initio theoretical investigations presented here adopted a one-electron picture, within the framework of Density functional theory, using the multiple scattering theory to solve the electronic structure problem. Most of the spectroscopies to be dealt with here can be seen as a direct consequence of the presence of a spontaneous magnetisation and relativistic effects, in particular the spin-orbit coupling. To deal with all relativistic effects and magnetism on the same level, the fully relativistic formalism will be used in the following. Thus, one of the goals of this work is to apply the Korringa-Kohn-Rostoker (KKR) band structure method in its relativistic version to a wide range of spectroscopies. Accordingly, all results will be compared with available experimental data as far as possible. Based on these results various aspects connected with experiments will be discussed in detail. In the first chapter the theoretical basis of this work will be introduced. The second part of this thesis is dedicated to the photoemission spectroscopies, i.e. spin-resolved Auger electron spectroscopy, Fano effects in valence band photoem ission and core level photoemission. In a third part we discuss resonant magneto-optical effects in the X-ray regime. Last chapter is dealing with non-collinear spin-structures within multiple scattering theory and its application to studies of photoemission and X-ray absorption is described.

The synchrotron light source is becoming widely available, after its evolution from its infancy in the sixties to the present third generation source with insertion devices. It is timely to examine the impact that synchrotron light has made and will continue to make on chemical research. With this objective in mind, the editor of this invaluable book invited contributions from practitioners who are in the forefront of the research. The book summarizes most of the significant developments in the last decade in chemical and related research using synchrotron light. The utilization of the light as a probe as well as an energy source is emphasized.This book is organized into two parts, in order of increasing photon energy. Part I deals with the applications of low energy photons and covers areas such as gas phase photodissociation reactions and dynamics, soft X-ray fluorescence, IR and photoemission analysis of surfaces, spectroscopy of organic and polymeric materials, catalysts, electronic and magnetic materials, and spectromicroscopy. Part II encompasses applications using soft to hard X-rays, including spectroscopy of surface and thin films, XAFS, diffraction and scattering, and several technological applications, namely the microprobe, photoetching and tribology.