Magnetic Behavior of Gadolinium Near the Curie Point

Magnetization measurements on a single crystal of gadolinium have established that the Curie temperature T_c is 292.5±0.5°K, that the initial susceptibility is given by ${\text{1/χ}}_0{\mathrm{=A(T-T}}_c{)}^{\frac{4}{3}}$ from T_c to 20° above T_c, and that the magnetization is given by σ=CH^¼ at T_c. These results are obtained only if measurements are made along the 〈0001〉 easy direction; measurements in other crystallographic directions give significantly different results because the magnetocrystalline anisotropy of Gd is not zero at and above T_c.