On the coupling between gadolinium 4f electrons and conduction electrons in monopnictides

The linear increase of the ESR linewidth with temperature has been measured for gadolinium in the metallic monopnictides MX where M=Sc, Y, La, Lu, and X=P, As, Sb, Bi. The Korringa relaxation rate was found to correlate with the lattice constant and with the covalency of the host compound. These correlations contribute to the understanding of the mechanism of the exchange coupling between the Gd 4f shell and the conduction electrons in these compounds.