P 56 Phase Relations in the Zn2V2O7–Cu2V2O7 System / T. I. Krasnenko, M. V. Rotermel', S. A. Petrova, R. G. Zakharov, O. V. Sivtsova, A. N. Chvanova // Russian Journal of Inorganic Chemistry. - 2008. - Vol. 53, № 10. - P1641-1647 : il. - Bibliogr. : p. 1647 (21 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ПИРОВАНАДАТЫ -- ФАЗОВЫЕ СООТНОШЕНИЯ Аннотация: Phase relations in the Zn2V2O7–Cu2V2O7 system were studied by high-temperature X-ray diffraction and differential thermal analysis. The major phase constituents of the system are solid solutions based on Zn2V2O7 and Cu2V2O7 polymorphs and their coexistence regions. The generation of α-Zn2 – 2xCu2xV2O7 solid solution, where 0 ≤ ı ≤ 0.30, leaves almost unchanged the stabilization temperature of the high-temperature zinc pyrovanadate phase. The α-Cu2 – 2xZn2xV2O7 homogeneity range is 5 mol % Zn2V2O7. In the range 0.050 ≤ ı ≤ 0.09 from 20 to ~ 620°ë, there is the two-phase field of α-Cu2V2O7 and β-Cu2V2O7 base solid solutions. At still higher temperatures, β-Zn2 – 2xCu2xV2O7 and α-Cu2 – 2xZn2xV2O7 coexist in the mixedphase region. β-Zn2 – 2xCu2xV2O7 solid solution, where 0 ≤ ı ≤ 0.30, exists above 610 ± 5°ë. The extent of the β'-Cu2V2O7-base solid solution is 9 to 65 mol % Zn2V2O7 at 615 ± 5°ë, expanding to 0 mol % Zn2V2O7 with rising temperature Полный текст |