| Реферат: | eng: Impurities and other defects in α-quartz not only record genetic information of this common mineral but also exert profound (positive or negative) effects on thetechnological applications of this important material. Also, fundamental defects in α- quartz often serve as the testing cases for understanding analogous defects in other silicabased materials. Following the last comprehensive review by Weil (2000), this contribution summarizes new progresses on the nature of paramagnetic impurities and other defects in α-quartz, made in the first decade of this century. In particular, new data on impurities stem from not only the development of in situ microbeam techniques for compositional analyses but also the application of state-of-the-art spectroscopic methods [high-frequency electron paramagnetic resonance (EPR), pulsed electron nuclear double resonance (ENDOR) and electron spin echo envelope modulation (ESEEM), and synchrotron X-ray absorption spectroscopy] and first-principles theoretical calculations for structural investigations. Other significant progresses include the discovery and quantitative characterization of a large number of new paramagnetic defects related to vacancies at the oxygen and silicon sites. © 2013 Nova Science Publishers, Inc. All rights reserved.
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