Previously obtained and certified HfO2 based samples were investigated by two Raman spectrometers with different wave source. Stokes reflexes have to be independent of the laser frequency so they were distinguished by comparison of different laser results. For the first time the dependence of Stokes lines frequencies on the cation radii of dopants was observed. Frequencies monotonically varied with the ratio of cation-dopant to hafnium radii changes. All non-Stokes reflexes are considered as photoluminescence. They were compared with both the literature data on luminescence of REM cations and the experimental results on zirconia-based materials intrinsic photoluminescence, which was a property of its point defects. Intrinsic photoluminescence is observed for the first time on hafnia-based materials.
Твердофазным методом синтезирован оксигаллат кальция Ca5Ga6O14. Установлено, что температура его плавления составляет 1325±2 °C. Обнаружен фазовый переход второго рода в температурном интервале 750-800 °C. Приведена температурная зависимость коэффициента термического линейного расширения в интервале 200-900 °C. Методами колебательной спектроскопии подтверждено, что структура Ca5Ga6O14 содержит не только GaO4 тетраэдры, но и GaO6 октаэдры.
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