Correlation factor in diffusion in the L1 2 structure for atomic migration via triple defects

Abstract

Expressions for the diffusion coefficients and correlation factors for diffusion by means of divacancies in compounds A 3B with the L1 2 structure are calculated. The divacancy is assumed not to dissociate and migrate via a triple-defect configuration. By applying a matrix method proposed by Howard [Phys Rev 1996;144:650], values for the correlation factors are calculated as a function of the ratio of the defect-atom exchange frequencies. The ratio of the diffusion coefficients of A and B atoms, D A/ D B, will lie between 0.061 and 4.9.