MAGNETIC-PROPERTIES OF TETRAGONAL YFE10.5MO1.5 SINGLE-CRYSTAL

Magnetic properties of the ferromagnetic YFe10.5Mo1.5 tetragonal compo und (T-c = 383 K) were measured on a single crystal. The spontaneous m agnetisation along the easy fourfold axis follows rather well the Lang evin function. The anisotropy within the basal plane remains negligibl e. The held dependence of the magnetisation perpendicular to c yields to the determination of the second-and fourth-order anisotropy constan ts K-1 and K-2 at any temperature below 300 K. At 10 K they reach 5.9 x 10(5) and 5.7 x 10(4) J/m(3), respectively. Besides, we compare the K-1 and K-2 determinations to those obtained from magnetisation measur ements on oriented powder.