STRUCTURE AND DYNAMICS OF MODEL METAL-CLUSTERS

The structure and dynamics of model metal clusters containing 13-55 atoms are investigated by molecular dynamics with regular quenching along the trajectory. The atoms interact via Sutton-Chen many-body potentials suitable for describing surface and bulk properties of gold and silver. The features of the potential energy surfaces of the clusters are elucidated by structural analysis of the quenched configurations and by eigenvector-following to find connecting transition states, and these features are related to the dynamical behavior. The observation of time-scale coexistence is shown to be strongly dependent upon cluster size as well as potential parameters. The Sutton-Chen silver and gold clusters have very different structural properties, with the silver potential stabilizing the icosahedral geometry, and the gold potential favoring glasslike structures. The results are compared with the available experimental observations.