A kinetic lattice gas model was applied to study collective surface diffusion of adsorbates on inhomogeneous surfaces. The diffusion coefficient was extracted from Monte Carlo simulations by observing the decay of the autocorrelation functions for density fluctuations. Calculations were presented for diffusion on a surface with various different coverages of randomly placed blocks and to diffusion on a surface with various distributions of traps of different binding energies. In the cases where analytical expressions for the collective diffusion coefficient could be derived, the Monte Carlo results showed excellent agreement with analytical predictions.

Monte Carlo Studies of Diffusion on Inhomogeneous Surfaces. C.H.Mak, H.C.Andersen, S.M.George: The Journal of Chemical Physics, 1988, 88[6], 4052-61