کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1519306 | 1511628 | 2006 | 5 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Local structure analysis of smoky and colorless topaz using single crystal 27Al NMR
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی مواد
مواد الکترونیکی، نوری و مغناطیسی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The angular dependence of the 27Al NMR spectrum was measured for single crystals of smoky and colorless topaz, Al2SiO4(F,OH)2. Smoky topaz was obtained by irradiating high energy neutrons to colorless topaz. The quadrupole coupling constant e2Qq/h and the asymmetry parameter η were obtained from the analysis of the angular dependences of quadrupole splitting of the 27Al NMR spectrum. The local structures around the aluminum atoms in smoky and colorless topaz were discussed from the magnitude and the direction of the electric field gradient. The directions of principal axes of the EFG tensor of 27Al were close to the directions of Al-O and Al-F bonds. The difference in the bond lengths between Al(1)-F(1) and Al(1)-F(2) was found to affect the x and y components of the EFG tensor.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Physics and Chemistry of Solids - Volume 67, Issue 4, April 2006, Pages 705-709
Journal: Journal of Physics and Chemistry of Solids - Volume 67, Issue 4, April 2006, Pages 705-709
نویسندگان
Motohiro Mizuno, Yoji Aoki, Kazunaka Endo, Darius Greenidge,