ANTIFERROMAGNETISM IN THE HO5OS4GE10 SYSTEM

In this paper, we report ac and dc susceptibility, resistivity, and he at capacity studies of the antiferromagnet Ho5Os4Ge10. We find that th is compound undergoes an antiferromagnetic transition at 2.1 K. The ef fective magnetic moment is found to be 10.85mu(B), which is slightly h igher than the free-ion value for the holmium atom. The resistivity [r ho(T)] shows unusual linear temperature dependence from 10 to 50 K. Fu rther, the heat-capacity data show an anomaly around 6 K, which is wel l above the antiferromagnetic ordering temperature. Absence of an anom aly in the magnetic susceptibility and a change of slope of rho(T) aro und this temperature suggest a possible structural transformation in t his compound although confirmation of this transformation requires fur ther study.