It was recalled that, in real solid and liquid metals, the temperature dependence of the diffusivity deviated from the Arrhenius law due to a lack of ideality. To a first approximation, this deviation could be described by a temperature correction to the Arrhenius law; which was similar to the pressure and volume corrections to the equation of state of a real gas. Therefore, the diffusion coefficient then took the form, D = Doexp[E/k(T+To)]. It was shown that this temperature dependence was confirmed by available experimental data on diffusion coefficients in solid and liquid metals.

Temperature Dependence of Diffusion Coefficient. R.L.Fogelson, E.R.Likhachev: Physics of Metals and Metallography, 2000, 90[1], 58-61