Structure and Bonding in Noncrystalline Solids

Noncrystalline (NC) solids, as is well known, lack the long­ range order of crystals. Accordingly, they exhibit scattering, e.g., x-ray, electron, and neutron, but not the diffraction patterns characteristic of crystals. The intensity distributions from NC solids are usually transformed into radial distribution functions (RDF), but the interpretation of the RDF's is not unique. The lack of long-range order, and the non-uniqueness of the structural interpretation, have constituted the main obstacles to the usual solid state physics approach which has been so successful in dealing with crystals. As a corrolary, questions of local order and structure have frequently been de-emphasized. This monograph contains a collection of chapters many of which emphasize local-structure and chemical bonding as opposed to long-range order. Most of the chapters were chosen from talks given at the international symposium, "Structure and Bonding in Noncrystalline Solids," held in Reston, Virginia in May of 1983. Other chapters, however, were simply submitted independently of the Reston conference. Thus, this book is not a proceedings of that conference, nor was it ever intended to be. The chapters presented here range from theory of bonding and structure, to structurally oriented measurements of various kinds, e.g., ESR, Raman, to more applied chapters. Our goal was to produce a monograph that enhances understanding of the structures of NC solids.