Magnetic, Electrical Properties and Spin-Glass Effect of Substitution of Ca for Pr in Ca2-xPrxMnO4 Compounds

Ca2-xPrxMnO4 (x = 0.000 to 0.200) manganites were synthesized by a sol-gel method and then characterized by X-ray diffraction (XRD) at room temperature. Rietveld refinement technique shows that all samples can be indexed in orthorhombic system except for Ca2MnO4 (x = 0.000) which can be indexed in the tetragonal system. Magnetic and electrical measurements show that magnetization and resistivity have a large dependence of the fractional composition x and temperature. The applied magnetic field has also a large influence on magnetization level. Spin-glass behavior was detected at low temperature for the samples with x≥0.175. For all x-values, all compounds exhibit semiconductor behavior and the ferromagnetic (FM) transition temperature TC (Curie temperature) is around 105 K, whatever the applied field.