Aggregation, deposition, and fragmentation of transition metal clusters

Abstract

With the aim of understanding the dynamic processes involved in the bonding and assembly of transition metal clusters, computer simulations have been performed of the aggregation of two clusters, the deposition of a cluster on a substrate of the same species, and the fragmentation of a cluster due to a high energy excitation. Monte Carlo and molecular dynamics techniques have been employed based on the many-body Gupta potential. It is demonstrated that the fusion of a 6- and a 7-particle cluster into a 13-particle system proceeds optimally if both initial reactants are at temperatures in the coexistence region between the solid and liquid states. The deposition of clusters on a (100) substrate of the same species is found to involve possible wetting transitions. Finally, evidence is presented that the fragmentation of 13-particle clusters leads to a size distribution function consistent with power-law behavior.