The electron paramagnetic resonance spectrum of singly ionized VTe revealed a cubic (unperturbed) symmetry, and the hyperfine structure showed that the unpaired electron was spread equally over the four Cd neighbors. Further ligand hyperfine interactions with more distant neighbors were resolved by using electron nuclear double resonance techniques. It was found that VCd was a double acceptor, and the electron paramagnetic resonance spectrum was observed in its singly negative charge state. The symmetry was trigonal, and was explained in terms of a model in which the hole occupied a dangling bond orbital and the orbital degeneracy was removed by a static Jahn-Teller distortion. The hyperfine interaction showed that the hole was localized on one of the four Te neighbors.

B.K.Meyer, D.M.Hofmann: Applied Physics A, 1995, 61[2], 213-5