Lattice dynamics and electron-phonon coupling in transition-metal diborides

Abstract

The phonon density of states of transition metal diborides $T{\mathrm{B}}_{2}$ with $T=\mathrm{Ti},$ V, Ta, Nb, and Y has been measured using the technique of inelastic neutron scattering. The experimental data are compared with ab initio density-functional calculations whereby an excellent agreement is registered. The calculations thus can be used to obtain electron-phonon spectral functions within the isotropic limit. A comparison with similar data for ${\mathrm{MgB}}_{2}$ and ${\mathrm{AlB}}_{2},$ which were subject of prior publications as well as parameters important for the superconducting properties are part of the discussion.