Magnetic anisotropy evolution of (Ce,Y)2Co17 compounds

The evolution of the magnetic anisotropy of (Ce,Y)2Co17 compounds with increasing Ce concentration was investigated by magnetic measurements and X-ray diffraction on magnetically aligned powders. At room temperature the easy magnetization direction changes from perpendicular to the c-axis to parallel to the c-axis with increasing Ce concentration. A spinreorientation transition from easy-axis anisotropy at higher temperatures to easy-plane anisotropy at lower temperatures arises at about 600, 530 and 320 K in Ce1.3Y0.7Co17, Ce1.5Y0.5Co17 and Ce1.7Y0.3Co17, respectively. The Curie temperature and spontaneous magnetization decrease with increasing Ce concentration. These magnetic behaviours are discussed in terms of the itinerant 4f states of Ce ion and the hybridization between the cobalt 3d states and the cerium 4f states.