Stability and Collapse of Metallic Structures on Surfaces

Abstract

Energetics, structure, stability, and collapse mechanisms of adsorbed gold clusters on Ni(100) and Au(111) surfaces were investigated with molecular dynamics simulations. Settling and spreading of Au clusters on Ni(100), driven by gain in cohesion and aided by the large interfacial lattice mismatch, are linear in time and occur via diffusionless sequences of atomic embedments between layers of the adsorbed cluster. Enhanced stability of epitaxial Au clusters on Au(111) was observed, and their collapse at elevated temperatures occurs via a dislocation mediated settling mechanism.