Following the irradiation of semi-insulating material at 4K, two new defect spectra were observed in the magnetic circular dichroism of the optical absorption. These were attributed to close Frenkel pairs. As well as the annealing of these close Frenkel pairs at about 200K, the well-known spectra of the PIn antisite and of a defect impurity complex were detected. The underlying defect reactions were considered with especial regard to correlations with the results of diffuse X-ray scattering investigations.

H.Hausmann, P.Ehrhart: Materials Science Forum, 1995, 196-201, 1261-6