Magnetic anisotropy of LuFe11Ti compound and its hydride and nitride

Magnetic anisotropy of LuFe11TiHx (x = 0, 1) single crystals and magnetical ly oriented powder samples of LuFe11TiNx (x = 1) were investigated. The ani sotropy study has been performed by means of torque and magnetization measu rements. The temperature dependencies of the magnetocrystalline anisotropy constants were determined using both least-squared fitting for the correcte d experimental torque curves and from the magnetization isotherms along the hard [100] direction using the Sucksmith-Thompson relation. The lattice pa rameters, Curie temperature and saturation magnetization are increased by b oth hydrogenation and nitrogenation. The easy c-axis anisotropy is enhanced in the hydrides but decreased in the nitrides. The volume expansion and ch ange of local environment of Fe ions after hydrogenation and nitrogenation lead to the effects observed. (C) 2001 Published by Elsevier Science B.V.