Crystal structure of the high-pressure form of BiVO4

Abstract

The crystal structure of BiVO₄, which has a monoclinic, distorted scheelite structure at ambient conditions, has been determined above the high-pressure transition at 1.6 and 4.3 GPa, and 23°C. At these pressures BiVO₄ has the tetragonal scheelite structure, which is also observed at high temperature above 250°C at room pressure. Vanadium tetrahedra remain rigid with no significant change in size at high pressure. Reduction of unit-cell volume is principally a result of Bi-O polyhedral compression. This behavior is similar to that observed for other scheelite-type compounds, in which tetrahedra are rigid and compression occurs in the 8-coordinated polyhedron.