H 65 High-Temperature Structural Disorder in R3NbO7 [Текст] / S. A. Kovyazina, L. A. Perelyaeva, I. A. Leonidov, Yu. A. Bakhteeva // Journal of Structural Chemistry (Translation of Zhurnal Strukturnoi Khimii). - 2003. - Vol. 44, № 6. - С. 975-979. - Библиогр. : с. 979 (20 назв.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): НИОБАТЫ -- ВИБРАЦИОННЫЕ СПЕКТРЫ -- ПИРОХЛОРЫ -- СТРУКТУРНЫЙ БЕСПОРЯДОК Аннотация: R3NbO7 (R=La, Nd, Gd, Y) niobates have been studied by Raman spectroscopy at 298-973 K. The temperature and composition effects on the structure of these compounds are considered. The changes observed in the Raman spectra at elevated temperatures are caused by a reversible structural disordering due to oxygen redistribution over anion sites. Полный текст |