Exploring the coordination change of vanadium and structure transformation of metavanadate MgV₂O₆ under high pressure.

ABSTRACT: Raman spectroscopy, synchrotron angle-dispersive X-ray diffraction (ADXRD), first-principles calculations, and electrical resistivity measurements were carried out under high pressure to investigate the structural stability and electrical transport properties of metavanadate MgV₂O₆. The results have revealed the coordination change of vanadium ions (from 5+1 to 6) at around 4?GPa. In addition, a pressure-induced structure transformation from the C2/m phase to the C2 phase in MgV₂O₆ was detected above 20?GPa, and both phases coexisted up to the highest pressure. This structural phase transition was induced by the enhanced distortions of MgO₆ octahedra and VO₆ octahedra under high pressure. Furthermore, the electrical resistivity decreased with pressure but exhibited different slope for these two phases, indicating that the pressure-induced structural phase transitions of MgV₂O₆ was also accompanied by the obvious changes in its electrical transport behavior.

SUBMITTER: Tang R 

PROVIDER: S-EPMC5141448 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature