Diffusion on anisotropic lattices of square and hexagonal symmetry

We calculate diffusion coefficients of many particles jumping over a few types of crystal lattices of square and hexagonal symmetry. Lattices differ by particle jump rates modified by the surface reconstruction or presence of some defects. We use the variational approach invented for the analysis of the collective diffusion coefficients. When all adsorption sites have the same energy and only the site blocking interactions are present, the collective diffusion coefficient is expressed by the same formula as the one for the single particle diffusion. Our calculations show in several examples how the arrangement of different jump rates along the lattice affects direction and character of the particle diffusion.