The influence of surface reconstruction on the diffusion of adsorbed particles was investigated within the framework of a simple 2-position symmetrical model. Exact expressions for the free energy and diffusion coefficient were obtained neglecting the lateral interaction between the adsorbed particles. The critical behavior of the system was described by an anisotropic Ising spin model. The coverage dependencies of the chemical diffusion coefficient were calculated for different temperatures and interaction parameters. The dependencies showed clearly the strong influence of the phase transitions, occurring in the system, on the particle migration. The chemical diffusion coefficient turns to zero at the critical points of the system.

Diffusion of Particles, Adsorbed on a Reconstructive Surface. A.A.Tarasenko, L.Jastrabìk: Surface Science, 2003, 532-535, 588-93