Theory for the Acoustic-Wave-Induced Electric Field Gradient in Transition Metals

Abstract

For transition metals I report the dependence of the acoustic-wave-induced electric field gradient (EFG) on $N(0)$, the electronic density of states at the Fermi-energy ${\ensuremath{\epsilon}}_{\mathrm{F}}$. It is shown that the EFG due to linear volume deformation of the unit cells of the crystal is proportional to ${N}_{s}(0)$, the $s$-electron density of states at ${\ensuremath{\epsilon}}_{\mathrm{F}}$, but does not correlate with $N(0)$ which is in general largely due to $d$ electrons. However, the EFG due to longwavelength shear waves correlates linearly with ${N}_{d}(0)$, the $d$-electron density of states at ${\ensuremath{\epsilon}}_{\mathrm{F}}$.