title: Some comments on the magnetic moments used in REFe2 exchange spring micro-magnetic simulations.
abstract: The current status of magnetic moments used in micro-magnetic modelling of the Laves phase rare earth iron REFe(2) inter-metallic compounds is reviewed. In particular, it is argued that both the neutron scattering results and band structure calculations provide little support for the long-held view that the Fe 3d moments are constant across the REFe(2) series, and for the oft-used rule of thumb that the (57)Fe hyperfine field is proportional to the Fe magnetic moment. Nevertheless, it is argued that it is acceptable to employ a simple ferrimagnetic model, in which the free-ion moment is ascribed to the RE ion and a moment of μ(d) = μ(3d) + μ(5d)≈1.5 µ(B) is used for the combined Fe(3d) and Fe-driven RE(5d) moments.
authors.affiliation: School of Physics and Astronomy, University of Southampton, Southampton, UK. gjb@phys.soton.ac.uk
authors.forename: G J
authors.initials: GJ
authors.lastname: Bowden
authors.forename: A R
authors.initials: AR
authors.lastname: Buckingham
authors.forename: G B G
authors.initials: GB
authors.lastname: Stenning
authors.forename: P A J
authors.initials: PA
authors.lastname: de Groot