Nonmajor cubic symmetry axes of easy magnetization in rare-earth-iron Laves compounds

Unusual [$uuw$]- and [$uv0$]-type axes of easy magnetization have been observed in some cubic rare-earth-iron Laves compounds. The presence of these directions of spontaneous magnetization can be accounted for, within the phenomenological treatment of the magnetic anisotropy, by including eighth-power direction-cosine terms in the power expansion of the magnetic anisotropy energy. It will also be shown that the single-ion model predicts the existence of these directions. The conditions imposed on the bulk magnetic anisotropy constants are derived. Typical values of these constants in rare-earth-iron Laves phases are calculated using the single-ion model.