Effect of Ce doping on the magnetic properties of LaCrO3

Polycrystalline samples of La1−xCexCrO3 (x=0 to 0.2) were prepared in single phase form by sol-gel route. The X-ray diffraction patterns could be refined by using Pbnm space group in orthorhombic cell. Systematic decrease in lattice parameters with increase in Ce concentration was observed. The doped samples exhibit a weak ferromagnetic (FM) transition in addition to the regular antiferromagnetic transition. As the doping concentration is increased, the FM transition temperature is found to increase from 40 K for x=0.05 to 135 K for x=0.15 and on the other hand, the Néel temperature is found to decrease. Onset of large coercivity along with peak like structure is observed as the sample is cooled through the FM transition. The observed FM is explained in terms of short range double exchange ferromagnetic interaction in Cr2+-O2−-Cr3+ networks.