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

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Abstract
The Knight shifts K of the Group IIIb metals Sc and Y alloyed with hydrogen, and T1T of Sc in the Sc-H system, have been determined and are compared with K and T1T of pure La, Y, and Sc and of La in the La-H system. It is found that KSc and T1TSc (in ScH2) are 0.07% and 25 sec-°K, respectively while KY (in YH2) is 0.11%. The ratio KMeH2KMe=0.33±0.03 for each metal Me=La,Y,orSc while T1TMeH2T1TMe=2.2×102. The similarity in the ratio of K's and T1T's is shown to suggest a similarity in the electronic band structure in the Group IIIb metals and their H alloys. The assumption of a large orbital contribution, dominating the s and d core polarization terms, to K and T1 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 K2T1T=ρ2(ℏ4πk)(γeγn)2, where ρ is explicity given as a function of the s, d, and orbital contributions. For the pure metals,