title: Structure of a high-pressure phase of vanadium pentoxide, beta-V2O5.
abstract: A high-pressure phase of vanadium pentoxide, denoted beta-V2O5, has been prepared at P = 6.0 GPa and T = 1073 K. The crystal structure of beta-V2O5 has been studied by X-ray and neutron powder diffraction, and high-resolution transmission electron microscopy. The V atoms are six-coordinated within distorted VO6 octahedra. The structure is built up of quadruple units of edge-sharing VO6 octahedra linked by sharing edges along [010] and mutually connected by sharing corners along [001]. This arrangement forms layers of V4O10 composition in planes parallel to (100). The layers are mutually held together by weak forces. beta-V2O5 is metastable and transforms to alpha-V2O5 at 643-653 K under ambient pressure. Structural relationships between beta- and alpha-V2O5, and between beta-V2O5 and B-Ta2O5-type structures are discussed. The high-pressure beta-V2O5 layer structure can be considered as the parent of a new series of vanadium oxide bronzes with cations intercalated between the layers.
authors.affiliation: Institute for High Pressure Physics, Russian Academy of Sciences, Troitsk, 142190 Moscow Region.
authors.forename: V P
authors.initials: VP
authors.lastname: Filonenko
authors.forename: M
authors.initials: M
authors.lastname: Sundberg
authors.forename: P-E
authors.initials: PE
authors.lastname: Werner
authors.forename: I P
authors.initials: IP
authors.lastname: Zibrov