Chemical Activity of Noble Gases in Diamond

Abstract

The matrix distortion influence on the noble gas atoms He and Ne introduced into diamond by ion implantation is discovered and explained. Consequences of the effect mentioned are the chemical activity of the noble gas atoms in diamond lattice and the formation of stable impurity-defect complexes, as it follows from the investigation of Mossbauer-type luminescence spectra.

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

“…Our assignment that the O N −V B be the observed GC-2 center is also consistent with the understanding that the GC-2 is a vacancy complex. In addition, the measured characteristic phonon frequency accompanied by the cathodoluminescence of the GC-2 center is about 56 meV [10,12] which is in excellent agreement with our theoretical estimate of 55 meV. Our density functional theory (DFT) calculations are carried out using the QUANTUM ESPRESSO package.…”

“…[9] It is suggested that GC-1 be vacancyrelated, while GC-2 be a vacancy complex. [9][10][11] The precise origin of these centers, however, have not been clearly identified. The measured energy of the ZPL of the GC-2 center agrees well with our theoretical value of 1.60 eV.…”

“…Experimentally, a characteristic phonon energy of about 56 meV is observed in the cathodoluminescence spectra of the GC-2 defect center. [10,12] Therefore, it would be very interesting to investigate the phonon structure of this defect center. Although rigorous quantum mechanical calculations of vibronic transitions of localized defect states is still not feasible today, the Franck-Condon principle provides a convenient theoretical foundation for identifying the local vibration modes (LVM) involved in electronic transitions.…”

“…[9][10][11][12][13] Experimentally, optical properties of defects in c-BN have been investigated using photoluminescence (PL) and cathodoluminescence (CL) techniques. [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.…”

“…For the GC-2 center, however, only the ZPL (1.63 eV) and the characteristic phonon frequency (56 meV) have been identified. [10,12] Theoretically, the optical transitions of defect states can be approximated by the total energy difference between the two electronic states involved within the Franck-Condon principle using the constrained DFT approach. For example, the energy of the vertical transition A→B (Fig.…”