Vacancy and interstitial configuration in hexagonal close packed metals

Abstract

Abstract The lattice static Green function and computer simulation methods are used in order to calculate the lattice distortion owing to a vacancy and a self‐interstitial in a hexagonal close packed lattice. A semidiscrete method is developed for the perfect lattice Green function evaluation. An empirical potential deduced by fitting magnesium parameters, and a pseudopotential, deduced for that metal, by Appapillai and Heine, are adopted for the calculation. The validity of using those potentials is discussed. An almost isotropic and very small lattice distortion is calculated for the vacancy, while a large and anisotropic lattice distortion calculated for an interstitial atom determines the trigonal (tetrahedral) configuration to be stable with respect to the hexagonal (octahedral) one.