GEOMETRY-DEPENDENT TRENDS IN THE SCATTERING OF VAN-DER-WAALS CLUSTERSFROM CRYSTAL-SURFACES

Classical molecular dynamics simulations of collisions of van der Waal s clusters with a rigid surface have been carried out. Several distinc t initial geometries of cluster were employed; in particular, constrai ned configurations in linear and ring geometries were used, as well as a fully minimized (polyhedral) structure. Both atomic and molecular ( diatomic) clusters were scattered. Our findings are that even at high collision energy a significant fraction of the constrained geometries survive the collision intact, or nearly so. This is, there is a measur able tendency for the survival to correlate inversely with the coordin ation number of the monomers in the cluster. There are also significan t differences in the angular scattering distributions, with the contra ined clusters tending to scatter nearer the specular angle. These find ings, together with the energy-transfer data available from the molecu lar cluster scattering, suggest this technique could find experimental use in distinguishing between clusters of low and high coordination.