MAGNETIC-ANISOTROPY IN UTX COMPOUNDS

The huge magnetic anisotropy in UTX compounds is found to be closely connected with the coordination of U atoms in closely connected with the coordination of U atoms in the crystal lattice. Generally, the easy magnetization direction is oriented perpendicular to the highest coordination plane or direction. The magnetization behaviour in ordered state yields effective anisotropy fields in the range 100-400 T. The anisotropy persists in the paramagnetic state where the values of the paramagnetic Curie temperature for the easy and hard magnetization directions differ by 100-400 K. The results are discussed in the framework of a model considering the anisotropic two-ion exchange interaction mediated by the 5f-ligand hybridization.