Structure and properties of some novel ternary Fe-rich rare-earth intermetallics (invited)

Abstract

The structures and the magnetic properties of some novel ternary compounds were studied. These compounds have the approximate composition RFe₁₀T₂, where T represents Cr, V, Ti, Mo, W, or Si. The structure of all these compounds can be derived from the tetragonal ThMn₁₂ structure type, but the crystallographic position occupied by the different T atoms is not the same. Most of the compounds have a homogeneity range represented by RFe_12−xT_x. This homogeneity range is fairly large in the case of T=V and strongly asymmetric for T=Ti and W. A structure determination is given for a representative member of the RFe₁₀Si₂ family. This structure determination is compared with results obtained previously for T=Mo and V, in which latter compounds the site occupancy of the T component is completely different from that in RFe₁₀Si₂. A survey is given of the magnetic and invar properties of RFe₁₀T₂ compounds. Special attention is paid to an analysis of the magnetocrystalline anisotropy in these materials.