9520554 Cohen This grant supports a long-range, broad based research program in condensed matter physics and materials science. The research projects cover the fields of semiconductors, metals, surfaces, defects, superconductivity, materials under pressure, clusters, fullerene-based materials, nanotubes, and many-body effects in solids. The major objective is to use quantum theory to explain and predict the properties of materials. Emphasis is placed on using realistic models, close collaborations with experimentalists, investigations and suggestions for producing novel and useful materials, development of new theoretical approaches, and predictions related to electronic and structural properties of solids. %%% This grant supports a long-range, broad based research program in condensed matter physics and materials science. The research projects cover the fields of semiconductors, metals, surfaces, defects, superconductivity, materials under pressure, clusters, fullerene-based materials, nanotubes, and many-body effects in solids. The major objective is to use quantum theory to explain and predict the properties of materials. Emphasis is placed on using realistic models, close collaborations with experimentalists, investigations and suggestions for producing novel and useful materials, development of new theoretical approaches, and predictions related to electronic and structural properties of solids. ***