An X-band electron paramagnetic resonance study was made of nominally pure diamond-like cubic crystalline powders. This led to the first identification of a spectrum which was attributed to 2 related paramagnetic species. The composite electron paramagnetic resonance spectrum could be observed only in dark brown powders, which were known to contain an excess of B. It consisted of 2 superposed Lorentzian components, D1 and D2, centred at 2.0063 and 2.0084, with peak-to-peak line-widths of 3.3 and 17.9mT, respectively. The temperature dependence of the integrated intensities, and their line-widths and D2/Dl intensity ratio led to the conclusion that the narrow line, Dl, originated from electron paramagnetic resonance transitions within a S = ½ ground doublet. The broad D2 line arose from transitions within the excited levels of another centre. The evidence suggested that both centres were B-related paramagnetic species.

EPR Observation of First Point Defects in Cubic Boron Nitride Crystalline Powders. S.V.Nistor, M.Stefan, D.Schoemaker, G.Dinca: Solid State Communications, 2000, 115[1], 39-44