ON THE INDUCED COBALT MOMENT IN RCO4B-TYPE COMPOUNDS

The results of magnetic measurements performed on (Gd//xY//1// minus //x)Co//4B compounds in the temperature range 4. 2-900 K are reported. The compounds with x greater than equivalent to 0. 2 are ferrimagnetically ordered. The mean cobalt moment is dependent on composition. Above the Curie temperatures, the reciprocal susceptibilities obey a nonlinear dependence as function of temperature. By using a two sublattice model, the mean values of the molecular field coefficients characterizing the magnetic interactions inside and between sublattices are determined. The mean cobalt moments are linearly dependent on the exchange fields acting on these atoms.