Electron spin resonance measurements of free-standing monocrystalline chemical vapour deposited diamond samples permitted the deduction of the symmetry of previously reported centers (KUL1, KUL3) as being trigonal and monoclinic-I, respectively. Based upon the correlation between the intensities of the KUL3 electron spin resonance signals and of the 1.68eV Si-related luminescence peak, and upon an analysis of the observed hyperfine interaction structure, the KUL3 center was suggested to involve one Si and one H atom. Two previously unreported centers, here labeled KUL16 and KUL17, were attributed to two <100>-oriented surface defects, each of which involved one H atom.

Characterization of Defects in Monocrystalline CVD Diamond Films by Electron Spin Resonance. K.Iakoubovskii, A.Stesmans, K.Suzuki, J.Kuwabara, A.Sawabe: Diamond and Related Materials, 2003, 12[3-7], 511-5