STUDY OF MAGNETIC HYPERFINE DATA ON RARE-EARTH IMPURITIES IN FE AND NI - NON-ORBITAL CONTRIBUTION

Hyperfine data on rare-earth impurities in the ferromagnetic transitio n host Fe and Ni are theoretically discussed, adopting a simple model, where one considers the local-charge perturbation and the next-neighb or perturbation due to the impurity. A self-consistent procedure enabl es us to calculate the hyperfine fields at the rare-earth sites in LuM , LaM and GdM(M = Fe, Ni), where no orbital contribution exists, and o ne gets a good agreement with experimental data. We also discuss the n on-orbital contribution and the sign of the total magnetic hyperfine h eld in cases where the orbital contribution is dominant as, e.g. EuM, TbM and YbM alloys. (C) 1998 Elsevier Science B.V. All rights reserved .