The authors’ theoretical work on dislocations in GaN was reviewed here. The methods used were 2 distinct approximations to density functional theory. One was a density functional based tight-binding total-energy calculation which permitted the prediction of low-energy core structures and the energies of extended defects which were embedded in larger regions of perfect material. However, when less approximate electronic structure calculations were required, they were obtained by using a localized basis pseudopotential approach.

A Theoretical Investigation of Dislocations in Cubic and Hexagonal Gallium Nitride. A.T.Blumenau, C.J.Fall, J.Elsner, R.Jones, M.I.Heggie, T.Frauenheim: Physica Status Solidi C, 2003, 0[6], 1684-709