Multiple Jumps and Vacancy Diffusion in a Face-Centered-Cubic Metal

The diffusion of monovacancies in gold has been studied by computer simulation. Multiple jumps have been found to play a central role in the atomic dynamics at high temperature, and have been shown to be responsible for an upward curvature in the Arrhenius plot of the diffusion coefficient. Appropriate saddle-points on the potential energy surface have been found, supporting the interpretation of vacancy multiple jumps as distinct migration mechanisms.