A study was made of Mg-O and Mg-VN defect complexes, in the cubic phase, by performing of ab initio calculations using a super-cell approach and the full-potential linear muffin-tin orbital method. Super-cells with 32 atoms were used, and atomic relaxations were taken into account. The positions of the defect levels, and formation energies, were calculated and compared with the results for individual defects. The calculations showed, in agreement with experimental data, that both of these complexes were energetically favourable, and were expected to play an important role in the self-compensation mechanism. Both types of complex introduced resonant states into the valence and conduction bands.

Mg-O and Mg-VN Defect Complexes in Cubic GaN I.Gorczyca, A.Svane, N.E.Christensen: Physical Review B, 2000, 61[11], 7494-8