Conduction Electron Polarization in Mixed Scandium Laves Phases with Cobalt and Nickel

Publisher Website
Google Scholar
Abstract
The Knight shift K and linewidth δH of the 45Sc NMR in the cubic Laves phase intermetallic system Sc(CoxNi1−x)2, where 0≤x≤1, have been investigated at 300°K. In accord with the probable simple Pauli paramagnetism of ScNi2, K=+0.39%, whereas in ScCo2, K=−0.43%, indicative of a d‐spin contribution to K from the Co° (d9) ions. In ScCo2, δH may be interpreted as resulting from the exchange‐narrowed dipolar field of the Co ions, with J/k=0.44°K. In the mixed compounds, δH varies linearly both with applied field H and composition x above and below x=0.5, and the average K varies smoothly, but not linearly, between the ScNi2 and ScCo2 values. The field and composition dependence of δH may be interpreted in terms of a distribution of K values resulting from the random distribution of Co neighbors. Preliminary measurements of the volume susceptibility indicate that the Knight shift and susceptibility may be directly correlated.