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ИСТИНА ФИЦ ПХФ и МХ РАН |
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Flux growth and characterization of NdTa7O19 crystalsтезисы доклада
- Авторы: Volkova E.A., Leonyuk N.I., Maltsev V.V., Cavalli E.
- Сборник: Abstr. Book of The Internat. Conference "Crystallogenesis and Mineralogy"
- Тезисы
- Год издания: 2001
- Место издания: St-Peterburg, Russia
- Первая страница: 422
- Аннотация: The crystalline NdTa7O19, NdTa3O9, Nd0.33TaO3, Nd1.67Ta5O15 and KTaO3 phases have been obtained. The typical sizes of the hexagonal plate-like crystals NHT with no significant inclusions were up to 2x2x1 mm3. These crystals belong to 6/m class of symmetry, and they have strongly developed faces of pinacoid, hexagonal prism and two hexagonal pyramids. A difference in the morphology of NHT crystals is depended on the chemical composition of fluxed melt. The size of pinacoid slightly increases with an increase in B2O3 concentration. With an increasing polymerization of borate anions in this system, the boron-oxygen polymers cause a significant structural blockage on the {0001} faces of the BO3-triangles in the structure of these crystals. The optical spectra of NdTa7O19 single crystals have been measured. These spectra are strongly affected by the presence of optically active ions at different non-equivalent optical centers. The number of components of the low temperature absorption and emission bands often exceeds that expected from the crystal field splitting of the electronic states of a single Nd3+ ions. At a room temperatures the band became broader. On the basis of the crystal growth and spectroscopy experiments, it can be concluded that the Nd-heptatantalate is a promising material with device potential.
- Добавил в систему: Леонюк Николай Иванович