COMPUTER EXPERIMENTS ON VACANCY INTERACTIONS IN GOLD.

An attempt was made to construct a pairwise, central force interatomic potential for gold which would give the monovacancy migration energy E sub m v1, the divacancy binding energy E sub B v2 and the elastic constants for the perfect crystal. It was possible to construct a potential which gives values for E sub M v1 and E sub B v2 that are uniformly about 20 percent less than those desired. A computer program DEFECT was written to compute vacancy interactions and vacancy-impurity atom interactions in cubic metals. During the course of testing the characteristics of several different potentials it was found that the variational method for defect configuration calculations will not necessarily converge for an arbitrary interatomic potential. Author