The potential energies of 2 coincidence grain boundaries, Σ = 7 and 19, were calculated by using a Stillinger-Weber potential which had been modified for wurtzite in order to take account of Ga-Ga and N-N wrong bonds. Their atomic structures, determined by high-resolution electron microscopy, were based upon 5/7 and 8 atom ring structural units. By using periodic boundary conditions, it was shown that the high-angle grain boundary, Σ = 7 (21°79/[00•1]), always had a smaller energy than that of Σ = 19 (13°17/[00•1]).

Energetic Calculation of Coincidence Grain Boundaries with a Modified Stillinger-Weber Potential. J.Chen, G.Nouet, P.Ruterana: Physica Status Solidi B, 2001, 228[2], 411-4