MAGNETIC-PROPERTIES OF XUCO5.3(1-X)UNI5 COMPOUNDS

The magnetic properties Of xUCo5.3(1-x)UNi5 compounds were studied in the temperature range 2-800 K and fields up to 70 kOe. UNi5 is a paramagnet. A peak in the temperature dependence of the magnetic susceptibility is observed at T almost-equal-to 20 K. The compounds with x greater-than-or-equal-to 0.2 are ferromagnetically ordered. The mean cobalt moments decrease from about 0.32 mu(B) for x = 1.0 to about 0.15 mu(B) for x = 0.2. Above the Curie temperatures the reciprocal susceptibilities show a Curie-Weiss-type behaviour. The effective cobalt moments are close to those of Co2+ ions. The experimental data are analysed in terms of the spin fluctuation model.