Cooperative Phenomena in Jahn--Teller Crystals

Sample

Hartmut Zabel, Stuart Solin

This book covers the basic physics and chemistry of graphite intercalation compounds. Emphasis is laid on the layered or quasi-two-dimensional structure of these compounds, which provides an exciting arena for testing physical concepts in lower dimensions. The chapters in this volume, all of which have been written by internationally recognized experts in the field, cover the following topics: the structure and phase transitions of intercalate atoms and molecules in graphite, the physics of staging formation and staging transitions, the lattice dynamics of these compounds as determined by inelastic neutron scattering and optical methods, the diffusivity of the guest species, mesoscopic properties such as domain structures and stacking arrangements, and the synthesis of new compounds. The reviews provide a comprehensive overview of the current status of the field of two- dimensional physics.

Sample

Charles W. Struck, William H. Fonger

This book gives a semiquantitative understanding of the properties observed in luminescence, i.e., where energy absorption and emission occur, and with what efficiency these conversion processes take place. The authors give a correct treatment of the offset dependence and the temperature dependence of nonradiative rates. The Wp function is defined as the sum of thermally weighted Franck-Condon factors. It is obtained in one dimension in several forms, and a useful recursion relation is derived between Wp's with nearby p indices. Two classes of applications are considered. First, an exposition of the broad classes of luminescence behavior is given and the Wp function and related functions are applied to each. Then the detailed application of these functions to specific experimental data, namely, to Eu3+, Tm3+, and Yb3+ in oxysulfides and oxychlorides and to Cr3+ in ruby is extensively discussed. The authors give a thorough review of the related literature. The many exact and approximate forms, some with certain errors, for Wp and related functions are listed and their relationship to Wp are given.

Sample

Kiyoyuki Terakura, Hisazumi Akai

Structural stability is of fundamental importance in materials science. Up-to-date information on the theoretical aspects of phase stability of materials is contained in this volume. Most of the first-principles calculations are based on the local-density approximation (LDA). In contrast, this volume contains very recent results of "going beyond LDA", such as the density gradient expansion and the quantum Monte-Carlomethod. Following the recently introduced theoretical methods for the calculation of interatomic potentials, forces acting on atoms and total energies such as the Car-Parrinello, the effective-medium and the bond-ordermethod, attempts have been made to develop even more sophisticated methods such as the order-N method in electronic-structure calculations. The present status of these methods and their application to real systems are described. In addition, in order to study the phase stability atfinite temperatures, the microscopic calculations have to be combined with statistical treatment of the systems to describe, e.g. order-disorder transitions on the Si(001) surface or alloy phase diagrams. This book contains examples for this type of calculations.

Sample

Clyde Arthur Morrison

A researcher trying to predict or interpret spectra of transition metal ionsin possible laser host materials is confronted with a variety of different methods of describing the same physical situation. This book provides a systematic approach to the applied theory of crystal-field interactions of transition metal ions in 49 crystalline hosts that are or show promise of being good laser materials. The tables that make up the main part of the book present the experimentally determined parameters of the 3dN, 4dN, and 5dN transition-metal ions in the second, third, and fourth ionization states. These parameters have been converted to Slater and crystal-field parameters. The book is a source for research workers in laser development and in crystal-field theory, and for graduate students of solid state chemistry and physics.