The interaction between 2 vacancies was investigated by means of molecular dynamics simulations. The concept of the capture radius was introduced, according to which the most stable configuration for a vacancy pair was a bound di-vacancy whenever the 2 defects were placed at distances that were smaller than the capture radius. An investigation was also made of the trapping mechanism of a monovacancy at a vacancy complex, together with the energetics of the early stages of aggregation of small vacancy clusters.

A.Bongiorno, L.Colombo: Physical Review B, 1998, 57[15], 8767-9