Professor R. Stephen Berry at the Department of Chemistry, University of Chicago, is supported by a grant from the Theoretical and Computational Chemistry Program at NSF for theoretical studies of atomic and molecular clusters. The work supported by this grant falls into four groups of related topics: (1) The dynamical properties of atomic and molecular clusters with emphasis on structural phases. (2) The chaotic and ergotic behavior of clusters. (3) The relationship between the topography of cluster potential energy surfaces and the formation of special cluster structures. Of special significance is the study of cluster sintering. Finally, (4) electron correlation in atoms and molecules, specifically including the study of 3 and 4 valence electron atoms. An omnipresent theme is that the theoretical studies are directly related to experimental studies. Clusters are special and unique forms of matter which lie between isolated atoms and molecules at one extreme and the solid state at the other extreme. While the properties of clusters are important for their own sake, they are also important because they bridge these two extremes. A long term objective of the cluster work which this grant supports is to understand how cluster properties determine, and ultimately merge with, bulk properties. The supported work integrates analytic theory, computation, and computer simulation into an approach with three primary goals: (1) deepening the understanding of commonplace properties of matter; (2) identifying new properties specific to matter at the scale of clusters and nanoscale particles; and (3) stimulating new experiments.
