D 26 Davydov, D. A. The Disorder–Order Transition in Cubic Vanadium Monoxide with Vacancies in the Metal Sublattice / D. A. Davydov, A. I. Gusev // Journal of Experimental and Theoretical Physics. - 2009. - Vol. 108, № 2. - P267-278 : il. - Bibliogr. : p. 277-278 (22 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): МОНООКСИД ВАНАДИЯ -- ПЕРЕХОД БЕСПОРЯДОК-ПОРЯДОК -- НЕСТЕХИОМЕТРИЯ Аннотация: The disorder–order transition in cubic vanadium monoxide VOy(y= 1.29, 1.30) possessing a B1 type structure and containing vacancies only in the metal sublattice has been studied by X-ray diffraction and symmetry analyses. It is established that the formation of a tetragonal (space group l41/amd) ordered V52O64phase in cubic vanadium monoxide VOyproceeds in the form of the first-order phase transition via a channel involving 22 nonequivalent superstructural vectors of four stars ({k10}, {k4}, {k3}, and {k2}). The distribution function of V atoms in the tetragonal V52 O64 superstructure is calculated, and it is found that the real ordered V51.6O64phase exhibits significant atomic displacements. The boundaries of the domain of existence of the V52O64 phase at 54–60% O are determined in the phase diagram of the V–O system Полный текст |