Magnetic properties of the 3d transition metals in the amorphous ternary alloys: Gd0.2(FexCo1-x)0.8, Gd0.2(CoxNi1-x)0.8, and Gd0.2(FexNi1-x)0.8

A systematic study was made of the magnetic properties of the amorphous alloys: Gd0.2(FexCo1-x)0.8, Gd0.2(CoxNi1-x)0.8, and Gd0.2(FexNi1-x)0.8. Results indicate that GdCo, GdNi, and GdCoNi alloys are collinear ferrimagnets involving electron transfer from Gd to the 3d elements. However, GdFe, GdFeNi, and GdFeCo alloys containing less than 30% Co are sperimagnetic due to antiferromagnetic interactions in the Fe subnetwork. Mean-field exchange energies are calculated and used to explain the results. A Slater-Pauling-type curve is constructed, and the dependence of properties on the average number of transition-metal 3d electrons is discussed. © 1980 The American Physical Society.