NMR analysis of an antiferromagnetic intermetallic rare earth compound

Zero field NMR of 139La probes in antiferromagnetically ordered GdAg was measured using phase-independent linear spin echo detection. Lineshape analysis gives information about the magnetic structure. 139La NMR of a Lasub(0.995)Gdsub(0.005)Ag single crystal in an external field yields hyperfine field contributions from distinct Gd neighbours, especially of the third nearest one. The comparison of both sets of data allows one to derive a negative sign of the transferred hyperfine field in the antiferromagnetic state. The investigation shows that indirect magnetic interaction via conduction electrons with RE-d character can lead to antiferromagnetic coupling. (Auth.)