Monte Carlo studies of diffusion on inhomogeneous surfaces

Abstract
A kinetic lattice gas model is applied to study collective surface diffusion of adsorbates on inhomogeneous surfaces. The diffusion coefficient is extracted from Monte Carlo (MC) simulations by observing the decay of the autocorrelation functions for density fluctuations. Calculations are 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 can be derived, the MC results show excellent agreement with analytical predictions.