It was recalled that, in natural diamonds, a sulfur-related paramagnetic center
labelled W31 had previously been tentatively attributed to an interstitial sulfur
species in a positive charge state. However it was shown here, by combining
available experimental data and density-functional simulations, that the hyperfine
tensors could be attributed to a defect made up of a sulfur at the center of a divacancy (so-called split vacancy), in the negative charge state. These acceptors
were very likely to be formed in S-implanted material and were a probable cause of
the high resistivity of samples implanted with sulfur in an attempt to produce ntype
conduction.
Electron Paramagnetic Resonance of Sulfur at a Split-Vacancy Site in Diamond.
J.M.Baker, J.A.Van Wyk, J.P.Goss, P.R.Briddon: Physical Review B, 2008,
78[23], 235203