PARAMAGNETIC BEHAVIOR OF CE1-XGDXCO2 COMPOUNDS

Magnetic susceptibility studies have been made on the cubic C15 (MgCu2 -type) Laves phases Ce1-xGdxCo2 in the temperature range 300-900 K. We ll above T-c, the inverse susceptibility follows a linear temperature dependence, as predicted by a phenomenological mean-field model descri bing a three-component ferrimagnetic alloy with localized magnetic mom ents. The values of the Curie constant determined in this way decrease regularly with x from x = 1 down to x = 0.4. Around x = 0.3, the Curi e constant exhibits a small local maximum. This suggests the onset of a spin-fluctuation regime at low x, possibly due to the reduction of t he internal field with the increase of cerium content.