The atomic structure of the 1/3<11•0> edge dislocation was simulated by using a Stillinger-Weber empirical potential which had been modified in order to take into account the homopolar bonds, Ga¯Ga and N¯N. The dislocation was characterized by a multiple structure which was based upon rings of 4, 8 or 5/7 atoms. This multiplicity was explained by considering the position of the origin of the displacements which corresponded to the creation of the dislocation. These displacements were imposed in accordance with isotropic linear elasticity theory. The choice of the origin was equivalent to considering the nature of the two {10•0} prismatic planes. The tips of these 2 planes formed the dislocation cores: the 5/7-atom ring for the lesser spaced planes and 4 or 8-atom rings for the more widely separated planes.

The Atomic Configurations of the ¯a Threading Dislocation in GaN. A.Béré, J.Chen, P.Ruterana, A.Serra, G.Nouet: Computational Materials Science, 2002, 24[1-2], 144-7