(La2/5Ba2/5Ca1/5)(Mn(2/5) : Rietveld studies, dielectric and magnetic properties of new perovskite-related oxides

[摘要] Oxides of the type (La_2/5Ba_2/5Ca_1/5) have been synthesized by the ceramic route. All the above oxides have been found to crystallize in the cubic perovskite structure. Rietveld refinement of the Ni-based oxide, (La_2/5Ba_2/5Ca_1/5)(Ni_2/5Ti_3/5)O₃ gave rise to a composition (La_0.44Ba_0.38Ca_0.18) (Ni_0.42Ti_0.58)O_2.85(6) and the refined lattice parameter obtained was 3.9411(2) Ã�?. A shift from antiferromagnetic to paramagnetic behaviour is observed with increase in nickel concentration, the Mn-rich phases showing antiferromagnetism around 5 K. There is a systematic decrease in the dielectric constant, and loss tangent with increase in Ni concentration .

[学科分类] 材料工程

[关键词] Oxides;Rietveld studies;dielectric.