The pre-exponential factors for self-diffusion via hopping and/or exchange on the (001), (110) and (111) surfaces of Cu, Ag and Ni were examined within transition-state theory. The calculations showed that the pre-factors had a weak temperature dependence above room temperature, and that within transition-state theory, the Vineyard method provided a rather accurate description of them. It was also found that the present approach was able to predict pre-factors to within the same precision as those obtained from molecular-dynamics simulations, and better than those derived from the thermodynamic properties when the contributions from the substrate were neglected.

Transition State Theory of the Pre-Exponential Factors for Self-Diffusion on Cu, Ag and Ni Surfaces. L.T.Kong, L.J.Lewis: Physical Review B, 2006, 74[7], 073412 (4pp)