Nuclear Magnetic Resonance and Magnetic Susceptibilities of V-Nb Alloys

Nuclear-magnetic-resonance properties of the ${\mathrm{V}}^{51}$ and ${\mathrm{Nb}}^{93}$ isotopes and magnetic susceptibilities are reported for V-Nb alloys. The magnetic susceptibility of V-Nb alloys decreases from 287 × ${10}^{-6\mathrm{}}$ emu/mole for pure V to 225 × ${10}^{-6\mathrm{}}$ emu/mole at 90 at.% Nb. The values of the square root of the nuclear spin-lattice relaxation rate ${\left(T_{1}T\right)}^{\frac{-1\mathrm{}}{2}}$ increase from pure V with increasing Nb concentration; ${\left(T_{1}T\right)}^{\frac{-1\mathrm{}}{2}}=1.12\mathrm{}$ ${\left(\mathrm{s}\mathrm{e}\mathrm{c}\mathrm{°}\mathrm{K}\right)}^{-1/2\mathrm{}}$ for V and ${\left(T_{1}T\right)}^{\frac{-1\mathrm{}}{2}}=1.55\mathrm{}$ ${\left(\mathrm{s}\mathrm{e}\mathrm{c}\mathrm{°}\mathrm{K}\right)}^{-1/2\mathrm{}}$ for the V-90 at.% Nb alloy. The ${\mathrm{V}}^{51}$ Knight shift increases from 0.564% in pure V to 0.602% in the 60 at.% Nb alloy, and then decreases slightly with increasing Nb concentration. The ${\mathrm{Nb}}^{93}$ Knight shift decreases from 0.821% in pure Nb to 0.688% in the 30 at.% Nb alloy, and then increases with increasing V content. The results are compared with that of other V and Nb transitionmetal alloys. It is found that the simple rigid-band model is inadequate to interpret the composition dependence of the NMR and susceptibility data.