کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5397791 1505873 2017 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Thermoluminescence in Lapis Lazuli crystal: Glow peaks and their connection with F-centers estimated by ESR analysis
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Thermoluminescence in Lapis Lazuli crystal: Glow peaks and their connection with F-centers estimated by ESR analysis
چکیده انگلیسی
The mineral Lapis Lazuli exhibits three thermoluminescence (TL) peaks approximately at 140, 260 and 370 °C. The TL intensity of the three peaks grows with radiation dose and it saturates only beyond 9 kGy. Electron Spin Resonance (ESR) studies have been carried out to identify the defect centers responsible for the thermoluminescence peaks. The ESR spectrum of the as-received natural sample presented the typical six signals due to Mn2+ ion and a large signal around g=2.030 due to Fe3+ ion. Room temperature ESR spectrum of irradiated Lapis Lazuli shows the formation of a defect center. This center (center I) is identified as an F+-center (singly ionized oxygen vacancy) and seems to correlate with 140 and 250 °C TL peaks. An additional defect center is observed during thermal annealing experiments and this center (center II - assigned to F+-center) appears to originate from an F-center (oxygen vacancy with two electrons). This F-center, precursor of center II, may be related to the observed high temperature 360 °C TL peak in Lapis Lazuli.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Luminescence - Volume 188, August 2017, Pages 472-477
نویسندگان
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