Stability and mobility of self-interstitials and small interstitial clusters in α-iron: ab initio and empirical potential calculations

摘要: Abstract The stability and mobility of self-interstitials small interstitial clusters, I n , in α-Fe is investigated by means calculations performed the framework density functional theory using SIESTA code. mono-, di- tri-interstitials are shown to be made (parallel) 〈1 1 0〉 dumbbells migrate nearest-neighbor translation–rotation jumps, according Johnson’s mechanism. 〈1 1 1〉 orientation becomes energetically more favourable for 5 larger clusters. performance a semi-empirical potential recently developed Fe, including ab initio self-interstitial data fitted properties, evaluated over present results. superiority previous potentials confirmed. Finally impact results on formation mechanism 〈1 0 0〉 loops, observed experimentally discussed.