Effective diffusion coefficients of point defects in impure materials

Abstract

Effective diffusion coefficients of vacancies and interstitials in a material containing impurities are derived in terms of impurity and point defect concentrations and reaction parameters. Irradiation and thermal conditions are considered. Several expressions presented earlier are reviewed. These are found to be limiting or approximate forms to a more general result. The regimes of importance of the point defect processes of thermal dissociation, trapping, recombination with bound point defects of the opposite type, and impurity-associated transport to sinks are evaluated in terms of the structure of the effective diffusion coefficients.