Electronic structure of oxygen-doped gallium arsenide

Using a multiple-scattering X alpha molecular cluster model, the authors studied the electronic structure of GaAs:O_As, including +or-5% symmetric relaxations of the nearest-neighbour atoms. Their results indicate that the oxygen impurity introduces a non-degenerate a₁ energy level in the crystal band gap. Their calculation leads to the conclusion that the oxygen impurity provokes an inward relaxation of the neighbouring atoms, and that Jahn-Teller distortions are not to be expected.