A model was developed which was based upon the Peierls framework for dislocations. The theory permitted the treatment of dislocations which were spreading on more than one slip-plane. Dislocation cross-slip and constriction processes were studied. The energetic parameters of the model were deduced from ab initio calculations. It was found that the screw dislocation split into partials and could not cross-slip without first being constricted. The dislocation constriction energy and the critical stress for cross-slip were determined and, from the latter, the cross-slip energy barrier for straight screw dislocations was estimated.

Dislocation Constriction and Cross-Slip - an ab initio Study. G.Lu, V.V.Bulatov, N.Kioussis: Physical Review B, 2002, 66[14], 144103 (5pp)