Enhancement of Ag cluster mobility on Ag surfaces by chloridation

To understand the role of chlorine in the stability and the observed fragmentation of Ag dendritic nanostructures, we have studied computationally two model systems using density functional theory. The first one relates to diffusion of Ag _n and Ag _n Cl _m (n 1-4) clusters on an Ag (111) surface, and the second demonstrates interaction strength of (Ag ₅₅)₂ dimers with and without chloridation. Based on our calculated energy barriers, Ag _n Cl _m clusters are more mobile than Ag _n clusters for n 1-4. The binding energy between two Ag ₅₅ clusters is significantly reduced by surface chloridation. Bond weakening and enhanced mobility are two important mechanisms underlying corrosion and fragmentation processes.