The chemical potential and the kinetics of the nearest-neighbor site-exclusion simple-cubic lattice gas were investigated using the Monte Carlo method. The existence of a second-order phase transition at a reduced density of 0.43 and with μ/kT = 0.06 was verified. It was shown that the Haven ratio exhibited a minimum at this second-order phase transition. Also calculated was the rigorous compositional form of the athermal lattice-gas ionic conductivity in comparison with fluorite-related oxides. The tracer-atom diffusivity was also calculated for qualitative comparison with light-atom diffusivities in interstitial alloys.

Diffusion in Highly Defective Solids - the Haven Ratio in the Athermal Lattice Gas. G.E.Murch: Philosophical Magazine A, 1980, 14[5], 701-11