Synthesis, structure analysis and magnetic properties of Ca2TiMnO6 oxides

Ca 2 TiMnO 6 compounds were synthesized by the conventional solid-state reaction in air. The crystal structure and magnetic properties were investigated. Characterization of X-ray diffractions and the refinement analysis confirmed the orthorhombic (space group Pbnm) structure of Ca 2 TiMnO 6 at room temperature. Magnetic measurements reveal that the double perovskite Ca 2 TiMnO 6 has antiferromagnetic interactions at low temperature and a paramagnetic order above 40 K. According to the Curie–Weiss fitting at high temperature, the Neel constant θ p and experimental efficient moment μ eff was estimated to be about −161.98 K and 4.91 μ B , respectively. The theoretical efficient moment was calculated to be 3.87 μ B . The XPS analysis indicates that the difference between experimental and theoretical efficient moment caused by the mixed valence state of Mn in Ca 2 TiMnO 6 . The temperature dependence of coercivity field shows a soft magnetic property in Ca 2 TiMnO 6 oxides. The mechanism of the low temperature anomaly which was appeared in magnetization curve was discussed in detail.