Volume III/28 is a supplement to volume III/16a+b Ferroelectrics and Related Substances. It also consists of two parts a and b. The present subvolume III/28a contains data on ferroelectric oxides, supplementing III/16a which appeared in 1981. Subvolume III/28b, due in 1990, will cover non-oxides, supplementing III/16b (published in 1982). Reliable data on both pure compounds and solid solutions, published mostly between 1978 and 1986 and some data from the literature up to early 1988 are critically evaluated and included. The dielectric and ferroelectric behaviour, as well as all other properties relevant to the characterization of these substances are presented in tables and figures. About 22,000 references have been surveyed with the aid of a computer. All values are given in SI units. Rapid localization of the required data is facilitated by an alphabetical index of substances and a two-dimensional survey of substances and properties dealt with in both subvolumes III/28a and III/16a.

The contents of this book stems from three different objectives. First, it is an introduction to the basic principles and techniques of Landau's theory, which is intended for teaching purposes. A second purpose of the book provides the practical methods for applying Landau's theory to complex systems. The last objective of the book is to incorporate the developments which have arisen in the last fifteen years from the extensive application of the theory to a variety of physical systems.

Many macroscopic properties of materials are determined primarily by inhomogeneous structures and textures. These intermediate-scale structures often arise from competing interactions operating on different length scales within the material. Our understanding of such phenomena has increased substantially with the identification and theoretical description of solid-state materials with incommensurate and long-period modulated phases, such as ferroelectrics, charge-density-wave compounds, epitaxial layers and polytypes. Experimental diagnosis of inhomogeneous ground states and metastable phases has advanced so far that these are now well-accepted phenomena. These proceedings bring together the work of physicists and materials scientists to review developments in this area and to examine possible future directions, such as how the microscopic understanding emerging in bench-top solid-state systems can be applied in materials science.

This volume in Advances in Physical Geochemistry presents the latest synthesis of theory and experimental data pertaining to structural and magnetic phase transitions in a variety of geochemically important minerals. The book is the first to cover the impact of this rapidly progressing area of solid state physics in earth sciences and reflects its growing significance for mineralogy and petrology.