Magnetic properties of ternary Fe-rich rare earth intermetallic compounds

The crystal structure and the magnetic properties are determined for several novel ternary intermetallic compounds of the type RFe₁₀T₂, where R represents Ti, V, Cr, Mo, W, or Si. All these compounds show a strong ferromagnetic behavior, with Curie temperatures in the range 350 K to 600 K. The magnetic and crystallographic properties of the RFe₁₀T₂ compounds are discussed together with the properties of 3d-rich ternary compounds of different composition and structure. Special attention is paid to the magnetocrystalline anisotropy of these materials, consisting of contributions of the R sublattice and the Fe sublattice. Detailed information on the crystal-field-induced contribution of the former sublattice is derived from ¹⁵⁵Gd Mossbauer spectroscopy performed on the Gd compounds of these series, since the ¹⁵⁵Gd nucleus can be regarded as a sensitive probe of the electric field gradient at the nuclear site produced by the electric charges of the surrounding ions. It can be shown that this electric field gradient is proportional to the second order crystal field parameter A⁰₂, which in turn determines the magnetocrystalline anisotropy of the R sublattice.