The diffusion was studied by using the moment method of statistical dynamics; including the anharmonicity effects of lattice vibrations. The Gibbs free energy of a metal lattice which contained thermal vacancies was derived by using the 4th-order moment approximation. The interaction energies between atoms in metals were estimated by using effective pair potentials. The activation energy and pre-exponential factor for self-diffusion were given in closed forms. The energy and factor were calculated for various metals at temperatures near to the melting temperature, and at liquid-He temperatures. They were shown to be in good agreement with the experimental results.

Study of Self-Diffusion in Metals by Statistical Moment Method - Anharmonic Effects. V.Van Hung, H.Van Tich, K.Masuda-Jindo: Journal of the Physical Society of Japan, 2000, 69[8], 2691-9