Molecular dynamics simulations of the stability and diffusion of 2 small clusters (Cu13 and Cu55), after soft deposition onto Au(111) surfaces, were performed by using a classical second momentum approximation tight-binding scheme. The studies revealed that the 3-dimensional cluster collapsed via a so-called solid-on-solid settling mechanism when a certain temperature was reached, and that diffusion of the 2-dimensional clusters depended strongly upon temperature and cluster size. Diffusion of the smaller cluster (Cu13) changed from simple uncorrelated random motion at low temperature to more complex motion at high temperatures, where the cluster diffused via 2 stages: correlated and uncorrelated random motion. Correlated motion was so enhanced in the case of the larger clusters (Cu55) that it could occur at lower temperatures.

Stability and Diffusion of Cu Clusters on Au(111) Surfaces. H.Lei: Physical Review B, 2002, 65[7], 075404 (6pp)