| Инд. авторы: | Nilges M.J., Pan Y., Mashkovtsev R.I. |
| Заглавие: | Radiation-induced defects in quartz. III. Single-crystal EPR, ENDOR and ESEEM study of a peroxy radical |
| Библ. ссылка: | Nilges M.J., Pan Y., Mashkovtsev R.I. Radiation-induced defects in quartz. III. Single-crystal EPR, ENDOR and ESEEM study of a peroxy radical // Physics and Chemistry of Minerals. - 2009. - Vol.36. - Iss. 2. - P.61-73. - ISSN 0342-1791. - EISSN 1432-2021. |
| Внешние системы: | DOI: 10.1007/s00269-008-0258-y; SCOPUS: 2-s2.0-59649094084; |
| Реферат: | eng: The X- and W-band single-crystal electron paramagnetic resonance spectra of an electron-irradiated natural quartz permit quantitative analysis of a 29Si hyperfine structure (A ∼12.6 MHz) and an 27Al hyperfine structure (A ≤ 0.8 MHz) for a previously reported hole-like center. The 29Si hyperfine structure arises from interaction with two equivalent Si atoms and is characterized by the direction of the unique A axis close to a Si-O bond direction. The 27Al hyperfine structure, confirmed by pulsed electron nuclear double resonance and electron spin echo envelope modulation spectra, is characterized by the unique A axis approximately along a twofold symmetry axis. These 29Si and 27Al hyperfine data, together with published theoretical results on peroxy radicals in SiO2 as well as our own density functional theory (DFT) calculations on model peroxy centers, suggest this hole-like center to have the unpaired spin on a pair of oxygen atoms linked to two symmetrically equivalent Si atoms and a substitutional Al3+ ion across the c-axis channel, a first peroxy radical in quartz. The nuclear quadrupole matrix P also suggests that the Al3+ ion corresponds closely to the diamagnetic precursor to the [AlO4]0 center. © pringer-Verlag 2008.
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| Ключевые слова: | quartz; crystallography; crystal structure; Crystal atomic structure; Single-crystal EPR; Peroxy radical; Hyperfine structures; ESEEM; ENDOR; DFT; Spin dynamics; Silicon compounds; Silicon; Resonance; Quartz; Quantum theory; Programming theory; Probability density function; Paramagnetism; Paramagnetic resonance; Oxygen; Oxide minerals; Nuclear magnetic resonance; Modulation; Irradiation; Electrons; Electron spin resonance spectroscopy; Electron resonance; Electron irradiation; Density functional theory; Atoms; Atomic physics; Aluminum; Single-crystal EPR; Quartz; Peroxy radical; radiation damage; ESEEM; ENDOR; Electron irradiation; DFT; Hyperfine structures; |
| Издано: | 2009 |
| Физ. характеристика: | с.61-73 |