Structure and magnetic properties of Gd2Co17−xCrx (1.17≤x≤3.0) compounds

Abstract: The structure and magnetic properties of Gd2Co17−x Cr x (1.17≤ x ≤3.0) compounds have been investigated by means of X-ray diffraction (XRD) and magnetization measurements. The powder X-ray diffraction patterns show that all samples crystallize as a single phase with the rhombohedral Th2Zn17-type structure. The lattice parameters a and the unit cell volume V increases slightly with increasing Cr content, but the c parameter varies in a less simple way with increasing Cr content. The X-ray diffraction patterns of the magnetically aligned samples show that all compounds investigated have uniaxial anisotropy. Spin reorientation phenomena occur in all of the compounds. The Curie temperature T C, the spin reorientation temperature T sr, the spontaneous magnetization M 0 and the saturation magnetization M s decrease with the increasing Cr content. The anisotropy constant K 1 and the anisotropy field B a of the compounds at room temperature reach a maximum for x =1.76. The M 0 and M s increase with increasing temperature from 5K to 300K. The easy-axis anisotropy of all compounds changes to easy-plane anisotropy at low temperatures and the spin reorientation phenomena are more pronounced for low Cr concentration. [Copyright &y& Elsevier]