D 26 Davydov, D. A. Ordered Monoclinic Vanadium Suboxide V14O6 / D. A. Davydov, A. I. Gusev // Physics of the Solid State. - 2009. - Vol. 51, № 1. - P156-164 : il. - Bibliogr. : p. 164 (22 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ОКСИД ВАНАДИЯ -- МОНОКЛИННАЯ СВЕРХСТРУКТУРА -- ТВЕРДЫЕ РАСТВОРЫ Аннотация: The monoclinic (space group C2/m) superstructure of the suboxide V14O6, which is formed as a result of the atomic and vacancy ordering of the tetragonal solid solution of oxygen in vanadium, is investigated using X-ray diffraction and symmetry analysis. The monoclinic suboxide V14O6 is observed in the vanadium oxide samples VO0.57, VO0.81, and VO0.86 synthesized at 1770 K and the samples VOy(0.87≤y≤0.98) additionally annealed at 1470 K after the synthesis. It is established that the channel of the disorder–order phase transition associated with the formation of the monoclinic suboxide V14O6 includes six superstructure vectors belonging to three non-Lifshitz stars of one type {k1}. The distribution function of the oxygen atoms in the monoclinic superstructure of the suboxide V14O6 is calculated. It is demonstrated that the displacements of vanadium atoms distort the body-centered tetragonal metal sublattice, thus preparing the formation of the facecentered cubic sublattice and the transition from the suboxide V14O6 to the cubic vanadium monoxide with the B1 structure Полный текст |