ESR characterization of point defects in amber colored c-BN super abrasive powders

Abstract

Cubic boron nitride (c-BN) crystalline superabrasive powder (Borazon ** CBN 400), consisting of 200 -300 microns sized amber colored crystallites prepared by HP/HT synthesis, has been examined from 2.1 K to 293 K by X-band ESR spectroscopy. The observed spectrum consists of a component line A1, visible in the whole temperature range, and two component lines A2 and A3, visible at high and low temperatures, respectively. The A1 and A3 lines originate from transitions inside S = 1/2 ground states of distinct paramagnetic species and A2 from transitions inside an excited state of another paramagnetic center. The intensity of the A1 and A3 lines changes differently during in situ low temperature illumination in the UV-VIS range.

Theory of Oxygen-Boron Vacancy Defect in Cubic Boron Nitride: A DiamondNV−Isoelectronic Center

“…[9][10][11][12][13][14][15] Identification of defect center in c-BN using electron spin resonance (ESR) experiments have also been reported. [16,17] Surprisingly, to the best of our knowledge, there has been no reported work using optically detected magnetic resonance to characterize defect centers in c-BN.…”