Knight Shifts and Relaxation Times in the GroupIIIbMetals and Metal-Hydrogen Systems

The Knight shifts $K$ of the Group $\mathrm{III}b$ metals Sc and Y alloyed with hydrogen, and $T_{1}T$ of Sc in the Sc-H system, have been determined and are compared with $K$ and $T_{1}T$ of pure La, Y, and Sc and of La in the La-H system. It is found that $K_{\mathrm{Sc}}$ and $T_1{T}_{\mathrm{Sc}}$ (in Sc${\mathrm{H}}_2$) are 0.07% and 25 sec-°K, respectively while $K_{\mathrm{Y}}$ (in Y${\mathrm{H}}_2$) is 0.11%. The ratio $\frac{K_{\mathrm{Me}{\mathrm{H}}_2}}{K_{\mathrm{Me}}}=0.33\mathrm{}\pm 0.03$ for each metal $Me=\mathrm{L}\mathrm{a},\mathrm{Y},\mathrm{o}\mathrm{r}\mathrm{S}\mathrm{c}$ while $\frac{T_1{T}_{\mathrm{Me}{\mathrm{H}}_2}}{T_1{T}_{\mathrm{Me}}}=2.2\mathrm{}\times {10}^2$. The similarity in the ratio of $K\text{'}\mathrm{s}$ and $T_{1}T\text{'}\mathrm{s}$ is shown to suggest a similarity in the electronic band structure in the Group $\mathrm{III}b$ metals and their H alloys. The assumption of a large orbital contribution, dominating the $s$ and $d$ core polarization terms, to $K$ and $T_1$ is shown to be consistent with the results. H alloying is interpreted in terms of hydrogen entering the metal interstitally as a bare proton, its electron being ionized and donated to the conduction band of the metal. A Korringa-like relation embodying $s$, $d$, and orbital effects is developed and shows a similarity in the band structure of La and Sc without considering H alloying. It is shown that $K^2{T}_{1}T={\rho }^2\left(\frac{\hslash }{4\pi k}\right){\left(\frac{{\gamma }_e}{{\gamma }_{\mathrm{n}}}\right)}^2$, where $\rho$ is explicity given as a function of the $s$, $d$, and orbital contributions. For the pure metals,