Antiferromagnetic transitions of osmium-containing rare earth double perovskites Ba2LnOsO6 (Ln=rare earths)

The perovskite-type compounds containing both rare earth and osmium Ba2LnOsO6 (Ln=Pr, Nd, Sm-Lu) have been prepared. An antiferromagnetic ordering of Os5+ ions has been observed for Ba2LnOsO6 (Ln=Pr, Nd, Sm, Eu, Gd, Lu) at 65-71 K. Measurements and analysis of the specific heat for Ba2PrOsO6 show that magnetic ordering of the Pr3+ moments should have occurred at ~20 K.