Magnetic dynamic effects in TbMn1-x(Ga/Sc)xO 3 samples (x=0.4, 0.5, 0.6)

The magnetic properties of strongly doped TbMnO3 with non-magnetic ions, such as Ga and Sc, has been studied focused in the intermediate region (0.4=x=0.6) where long range ferromagnetic ordering was reported for La-based compounds. All samples are single phase and show a perovskite structure with orthorhombic unit cell, space group Pbnm. The Tb-based compounds do not show long range magnetic order but magnetic anomies are noticeable at low temperature. These anomalies show magnetic irreversibility and dynamic effects typical of magnetic glassy systems. These features have been studied in detail using ac magnetic susceptibility and the analysis shows the largest magnetic correlations for x=0.5 in both type of substitutions