Following the diffusion of Ag into p-type material at room temperature, 2 electric-field gradients were detected at 111In/111Cd probe atoms at 77K. The attribution of one of these gradients to In-A centers led to the conclusion that the 0/- level of the Cd vacancy was located deeper in the band-gap than the shallow doping, and that the 2 electric-field gradients were caused by the neutral and singly-negative Cd vacancy.

U.Reislöhner, N.Achtziger, M.Rüb, W.Witthuhn: Journal of Crystal Growth, 1996, 159, 372-5