| Инд. авторы: | Volkov S.N., Filatov S.K., Bubnova R.S., Ugolkov V.L., Svetlyakova T.N., Kokh A.E. |
| Заглавие: | Thermal expansion and order-disorder polymorphic transformation in the family of borates BaNaMe(BO 3) 2, Me = Sc, y |
| Библ. ссылка: | Volkov S.N., Filatov S.K., Bubnova R.S., Ugolkov V.L., Svetlyakova T.N., Kokh A.E. Thermal expansion and order-disorder polymorphic transformation in the family of borates BaNaMe(BO 3) 2, Me = Sc, y // Glass Physics and Chemistry. - 2012. - Vol.38. - Iss. 1. - P.162-171. - ISSN 1087-6596. - EISSN 1608-313X. |
| Внешние системы: | DOI: 10.1134/S108765961201018X; SCOPUS: 2-s2.0-84857766926; |
| Реферат: | eng: The thermal behavior of BaNaMe(BO 3) 2, Me = Sc, Y (space group R-3) is studied by the methods of high-temperature X-ray powder diffraction, differential scanning calorimetry, and thermogravimetry in the range from room temperature to 1300°C. It is shown that a polymorphic transition with a two-fold reduction of the unit cell volume is observed at 775 ± 20°C (Sc) and 375 ± 30°C (Y). New polymorphic modifications are solid solutions (Ba, Na)Me(BO 3) 2, (Me = Sc, Y) with a disordered distribution of Ba and Na atoms. Eigenvalues of the thermal expansion tensor of the polymorphic modifications are calculated for BaNaSc(BO 3) 2 and BaNaY(BO 3) 2. The solid solutions are stable approximately up to 819°C (Sc) and 770°C (Y); at higher temperatures, the solid-state decomposition of these phases begins. © 2012 Pleiades Publishing, Ltd.
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| Ключевые слова: | Na atoms; Polymorphic modifications; Polymorphic transformation; Polymorphic transitions; Room temperature; Solid-state decomposition; Space Groups; Thermal behaviors; Thermal-expansion tensors; Two-fold reduction; Unit-cell volume; Barium; Differential scanning calorimetry; Eigenvalues and eigenfunctions; Sodium; Solid solutions; Thermal expansion; Thermogravimetric analysis; Order disorder transitions; X ray powder diffraction; High temperature; Eigenvalues; Disordered distribution; borates BaNaMe(BO 3) 2; thermal expansion; thermal behavior at heating to 1300°C; polymorphic transformations; Me = Sc, Y; Higher temperatures; borates BaNaMe(BO 3) 2; |
| Издано: | 2012 |
| Физ. характеристика: | с.162-171 |