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arXiv · 0704.0696

Phonon instability and structural phase transition in Vanadium under high pressure

Ashok K. Verma·P. Modak
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Abstract

Results of the first-principles calculations are presented for the group-VB metals V, Nb and Ta up to couple of megabar pressure. An unique structural phase transition sequence BCC-->(at 60 GPa) rhombohedral (angle=110.5 degree)-->(at ~ 160 GPa)rhombohedral(angle=108.5 degree)--> (at ~ 430 GPa) BCC is predicted in V. We also find that BCC-V becomes mechanically and vibrationally unstable at around 112 GPa pressure. Similar transitions are absent in Nb and Ta.

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Ashok K. Verma, P. Modak. 2007-04-05. Phonon instability and structural phase transition in Vanadium under high pressure. https://doi.org/10.1209/0295-5075/81/37003

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