Structural phase transition in vanadium at high pressure and high temperature : Influence of nonhydrostatic conditions

Vanadium has been reported to undergo phase transition upon compression from body-centered cubic (bcc) to rhombohedral structure around 62 GPa. In this paper we confirm the bcc to rhombohedral phase transition at 61.5 GPa under quasihydrostatic compression in the Ne pressure medium. Under the nonhydrostatic condition we find the phase transition occurring at 30 GPa at ambient temperature and 37 GPa at 425 K. We find the transition under the hydrostatic condition is hindered and it can occur at much lower pressure under the nonhydrostatic condition.