Тип публикации: статья из журнала
Год издания: 2010
Ключевые слова: Asymmetry parameter, Coupling constants, Dielectric studies, Larmor frequencies, Line shape, Reasonable accuracy, Solid solution structures, Temperature range, C (programming language), Nuclear magnetic resonance spectroscopy, Phase diagrams, Sodium, Tantalum oxides, Solid solutions
Аннотация: The heat capacity of NaNb1_xTaxO3 solid solutions was measured in the temperature range 100 to 770 K. The step-like change of phase transition temperature is observed in the T-x phase diagram at concentration x = 0.55. The obtained results are in a good agreement with the data of dielectric studies. The 23Na MAS NMR spectra were obПоказать полностьюtained at Larmor frequency 79.35 MHz using a Bruker AVANCE 300 spectrometer. The quadru-polar coupling constant, (CQ=e2qQ/h) and asymmetry parameter (n) were determined by computer fitting of the NMR line shape using the DMFit software. The found parameters show that solid solution structure is NaTa03-based at 0.7X ?1 and NaNbO3-based at 0?x?0.5. The spectra in the intermediate region (0.5x?0.7) can be described at a reasonable accuracy when assuming the coexistence of NaTaO3 and NaNbO3 structures. © 2010 - STC "Institute for Single Crystals".
Журнал: Functional Materials
Выпуск журнала: Vol. 17, Is. 1
Номера страниц: 18-23