Pseudopotential Theory of Formation Energies and Volumes of Point Defects in Metals

Abstract

Pseudopotential theory is applied to calculate the formation energies and the formation volumes of point defects in metals: a vacancy, a self-interstitial atom and a Frenkel defect. The structural part of the formation energy is expressed by a sum of two terms, as Faber's formula for the vacancy formation energy is done; one is related to a change in the lattice sum of the pair interaction potential between ions due to change in the arrangement of ions around the defect, and the other is done to that due to change in the lattice size parameter. Then the formation energy and volume that take account of relaxation effects are formulated. Finally a numerical calculation is carried out of the structural parts of formation energies and volumes of vacancies and self-interstitial atoms in the alkali metals.