Diamond and related materials vol:12 issue:3-7 pages:511-515
Electron spin resonance (ESR) measurements on free-standing monocrystalline CVD diamond samples allowed us to deduce the symmetry of the previously reported KUL1 and KUL3 centers as trigonal and monoclinic-I, respectively. Based on the correlation between the intensities of the KUL3 ESR signals and of the 1.68 eV Si-related luminescence peak, and on the analysis of the observed hyperfine interaction structure, the KUL3 center is suggested to involve one Si and one hydrogen atom. Two previously undocumented centers, labeled as KUL16 and KUL17, have been characterized and attributed to two <100>-oriented surface defects, each involving one hydrogen atom. (C) 2003 Elsevier Science B.V. All rights reserved.