Theoretical study on the lattice dynamics and electron–phonon interaction ofvanadium under high pressures

Abstract

First-principles calculations are performed for the lattice dynamics andelectron–phonon interaction of the body-centred-cubic (bcc) phase of solidvanadium.A remarkable phonon anomaly is found, i.e. frequencies of the transverse mode around a quarterof the Γ–Hline show softening with increasing pressure and become imaginary at pressureshigher than ∼130 GPa.The superconducting transition temperaturesTcof bcc vanadium estimated as a function of pressure increasesat first linearly with pressure, and then the rate of increase ofTc isabated around 80 GPa.This calculated pressure dependence ofTcshows qualitatively the same behaviour as the experimental result.