MD STUDIES OF THE INTERACTIONS OF LOW-ENERGY PARTICLES AND CLUSTERS WITH SURFACES

The interaction of low-energy particles and clusters with metal surfac es has been investigated using molecular dynamics computer simulations . For the particle interactions, a new mechanism for producing damage at surfaces was revealed in simulations of 10 and 20 keV Au bombardmen t of Au surfaces. Macroscopic modeling of this phenomenon illustrates the important parameters. For the cluster interactions, many different clusters and substrates were employed: the energies were varied from less than one eV (soft landings) to over 3 keV; the size of the cluste rs was varied from 87 to 1000, the angle of incidence was varied from near glancing to near normal, and both solid and liquid clusters were examined. Embedded atom method potentials were employed to represent t he different metals and alloys. A broad range of behavior was observed in the simulations: splatting of the cluster over the surface, the fo rmation of globs, the penetration of the clusters deep into the substr ate. General rules are suggested for predicting which type of behavior prevails.