The core structure of a screw dislocation in a diamond lattice was calculated by using a Stillinger-Weber potential for the interatomic interactions. A non-dissociated screw dislocation, positioned at the centre of a unit hexagon normal to the dislocation line, was a stable configuration (A). A perfect screw dislocation, centred on the longer edge of the unit hexagon was also a stable configuration (B). The latter was more stable, and had a lower energy than that of configuration-A. Dissociated configurations with width, na (where a was the repeat distance in the slip direction and n = 1, 2, 3 ...), were also stable. The Peierls stress of the perfect screw dislocation was 0.044G, where G was the shear modulus.

Core Structure of a Screw Dislocation in a Diamond-Like Structure. H.Koizumi, Y.Kamimura, T.Suzuki: Philosophical Magazine A, 2000, 80[3], 609-20