Transition state theory of the preexponential factors for self-diffusion on Cu, Ag, and Ni surfaces

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