The motion of peripheral atoms of an Ir18 cluster, which results in migration of the cluster on Ir(111), was studied by kinetic Monte Carlo simulations. Detailed moving processes of individual peripheral atoms of the cluster were proposed. Statistical average of staying times showed that these atoms basically located only at several energetically equilibrium positions, which made the motion of atoms effectively in a form of jumping of dimer from one equilibrium position to another. The jumping of the dimers, which results in migration of the cluster, were further simulated by introducing effective energy barriers between these equilibrium positions. A temperature dependence of the diffusivity D for the migration of the cluster was in good agreement with the experimental results, which proved the suitable values of the effective energy barriers for the motion of the dimers

The Atomic Moving Processes of Cluster Ir18 Diffusion on Ir(111). G.Zhuang, W.Wang: International Journal of Modern Physics B, 2000, 14[4], 427-34