Conditions for the formation of a non-autonomous phase at the structural deformation of complex vanadium oxides

Abstract

A new previously unknown effect of a reversible transition from a single-phase system to a heterophase system containing a non-autonomous phase was observed during thermal and chemical deformations of the Zn2-2xCd2xV2O7 structure.The role of local symmetry in the formation of the non-autonomous phase is shown on the basis of X-ray diffraction studies in situ and a comparative crystal-chemical analysis of the structural deformations of isoform monoclinic solid solutions of zinc and copper pyrovanadates with zero volumetric thermal expansion.

Keywords

• non-autonomous phase
• volume thermal expansion
• M2V2O7