Nuclear-Acoustic-Resonance Determination of the Electronic Contribution to the Electric-Field-Gradient Tensor in Molybdenum

Nuclear acoustic-resonance absorption and dispersion of both isotopes ${\mathrm{Mo}}^{95}$ and ${\mathrm{Mo}}^{97}$ have been observed for the first time in molybdenum. From quantitative evaluation of the nuclear-acoustic-resonance results in the conduction-electron contribution to the tensor $\overleftrightarrow{\mathrm{S}}$ connecting the electric field gradient to elastic strains have been determined at high magnetic fields. Comparison of the electronic contributions to the diagonal and offdiagonal elements of the electric-field gradient in Mo, Ta, and Nb show a disparity in the dependence on the density of states.