Study of the crystal field and exchange interactions in single crystal hydride HoFe sub 11 TiH

The influence of the hydrogen absorption upon structural and magnetic properties of single crystals HoFe sub 11 Ti have been studied. It was observed that the hydrogenation leads to a crystal lattice expansion of the compounds without change of a tetragonal structure of the ThMn sub 12 -type. Magnetization measurement along the main symmetry direction of the tetragonal structure have been performed on RFe sub 11 TiH sub X (x = 0, 1) single crystals at applied high magnetic fields up to 80 kOe in temperature range from 4.2 K to 300 K. Torque measurements were carried out in the temperature range 78-700 K in magnetic fields up to 13 kOe. The analysis of the temperature dependence of torque curves allowed to investigate spin reorientation transitions in RFe sub 11 TiH sub X single crystals. A set of CEF parameters and mean exchange field has been obtained for HoFe sub 11 TiH single crystal.