A Monte Carlo investigation was made of tracer and conductivity correlation factors in a simple-cubic lattice-gas having two fcc inequivalent sub-lattices and self-exclusion by the atoms. Except at very low temperatures, excellent agreement was found between these results, for the conductivity correlation factor, and Richard's approximate treatment. At an occupation of 0.5, the Haven ratio exhibited the characteristic discontinuity found in other lattice gases which gave ordered arrangements. On the concentration axis at low temperatures another discontinuity was found in the Haven ratio. All of these discontinuities were associated with mechanism changes.

Correlation Effects in Diffusion in a Two Sublattice Structure. G.E.Murch: Journal of Physics and Chemistry of Solids, 1982, 43[3], 243-7