Pressure-induced transitions between the A1() and A1(L) substitutional SiGa donor states were calculated by using the tight-binding approach. There were no energy barriers to such transformations; in agreement with experimental results. It was suggested that the DX state of this donor arose from the T2(L) resonant state, as a result of spontaneous tetragonal distortions.

S.W.Biernacki: Semiconductor Science and Technology, 1996, 11[1], 17-21