Local-density-functional calculations for defect interactions in Al

We present systematic ab initio local-density-functional calculations for defect interactions in Al. In particular, we calculate interaction energies of both impurity-vacancy and impurity-impurity pairs on first- and second-neighbor sites; as impurities, we choose Sc-As (3d and 4sp series) and Y-Sb (4d and 5sp series). The present method is based on the Kohn-Kofiinga-Rostoker Green's-function method. The calculations reproduce well the experimental values for the vacancy-solute interaction and elucidate the micromechanisms of the vacancy-impurity and impurity-impurity binding energies.