Modeling diffusion on heterogeneous lattices: Simple cubic lattice

摘要

In our previous work, general analytical expressions for the chemical and jump diffusion coefficients have been derived in the case of strong inhomogeneity for lattices of different symmetries and dimensionalities. It has been shown that the character of the particle migration depends crucially on the relative jump frequencies of particles located in deep and shallow sites. If these frequencies differ insignificantly, particle diffusion proceeds by single uncorrelated jumps, while widely differing jump frequencies result in pairs of strongly correlated jumps. We have checked the expressions for the case of square inhomogeneous lattice using kinetic Monte Carlo simulations. Here, we present results of particle migration over three-dimensional inhomogeneous simple cubic lattice. The density dependences obtained by the analytical expressions for different temperatures and signs of the lateral pairwise interaction are compared with the results of the direct kinetic Monte Carlo simulations of the particle diffusion. Almost perfect agreement between the respective results has been found.