Investigation of the magnetic properties of the perovskite Ba3PrRu2O9 using muon spin relaxation

The perovskites containing both ruthenium and lanthanide ions are of particular interest for the study of magnetic cooperative phenomena due to interactions between d and f electrons. We have performed the magnetic susceptibilities, specific heat, and neutron diffraction measurements on D20 at ILL for Ba3PrRu2O9 polycrystalline sample. It was found that a Pr4+ antiferromagnetic transition occurred at around 5 K and that Ba3PrRu2O9 showed magnetic behavior due to the Ru4+2O9 dimer in the higher temperature range. The magnetic susceptibility increases with a temperature above 200 K. However, this behavior cannot be explained by the dimer model. Powder neutron diffraction measurements at 2 K do not show clear magnetic brag peaks. In order to further clarify the magnetic ground state of Ba3PrRu2O9, we proposed to carry out µSR measurements on EMU/HiFi.