Crystalline electric field in NdxSm1-xCo5 compounds

The values of the crystalline-electric-field parameters and the exchange field for the Nd and Sm ions in NdxSm1-xCo5 (x=0.00, 0.20, 0.30, 0.37, 0.50, 0.60, 0.75, 0.88 and 1.00) compounds are evaluated by comparing the calculations with experiments on a series of single crystals of the compounds. The experiments provide the following data: temperature dependence of the spontaneous magnetization, temperature depenence of the cone-angle between the magnetic easy-direction and the c-axis, and magnetization curves at different temperatures. A20 for the Sm ion decreases slightly with increase of temperature, while A20 for the Nd ion decreases apparently, which is slightly affected by the composition x. The coercivity of the domain wall movement in a crystallite during a first order magnetization process is of the intrinsic one which is intimately related to a fluctuation of the magnetic anisotropy and the exchange interaction in a microscopic scale. (orig.)