Calculations of the geometry and electron structure of self-interstitial atoms were performed, within the cluster approximation, by using self-consistent discrete variational and molecular dynamics methods. The results of the former calculations showed that a high state density in the band gap, and various spin states, were observed for interstitial complexes. Methods which involved neglecting the differential overlapping could not be used to provide a satisfactory analysis of self-interstitial atom properties. The molecular dynamics calculations proved the existence of a new stable configuration. This was oriented in planes which were equivalent to (110), and contained a pair of self-interstitials in a tetrahedral cavity.

G.S.Myakenkaya, G.L.Gutsev, N.N.Gerasimenko, V.V.Frolov, M.A.Chubisov, J.W.Corbett: Radiation Effects and Defects in Solids, 1994, 129[3-4], 199-216