کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1476403 1510146 2007 4 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Raman scattering study of the high temperature phase transitions of NaTaO3
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Raman scattering study of the high temperature phase transitions of NaTaO3
چکیده انگلیسی

The phase transition sequence of sodium tantalate (NaTaO3) ceramic samples has been investigated by Raman spectroscopy, from room temperature up to 640 °C. At room temperature, NaTaO3 shows an orthorhombically distorted perovskite structure belonging to the Pbnm space group. Raman and infrared vibrational spectra at 20 °C are in relative good agreement with group theory predictions for this group. At high temperatures, NaTaO3 shows three phase transitions, in the sequence Pbnm (∼450 °C) Cmcm (∼560 °C) P4/mbm (∼620 °C) Pm3¯m. The Raman spectra for the two intermediate high temperature phases showed a decreasing of the number of the active modes, accompanied by band broadening, and were well compatible with structural symmetry increasing at higher temperatures.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of the European Ceramic Society - Volume 27, Issues 13–15, 2007, Pages 3683–3686
نویسندگان
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