Enhanced spin reorientation temperature and origin of magnetocapacitance in HoFeO3

We report on the increase in the spin reorientation temperature in HoFe0.5Cr0.5O3 compound by isovalent substitution Cr3+ at the Fe-site and the magnetocapacitance in the HoFeO3 compound. Spin reorientation transition is evident around 50 K and 150 K for the x = 0 and x = 0.5 compounds respectively. The increase in the spin reorientation transition temperature in case of x = 0.5 compound can be attributed to the domination of the Ho3+ to Fe3+ interaction over the Fe3+ to Fe3+ interaction. Decrease in Neel temperature from 643 K (x = 0) to 273 K (x = 0.5) can be ascribed to the decrease in the interaction between antiferromagnetically aligned Fe3+ moments as a result of the dilution of the Fe3+ moments with the Cr3+ addition. From the magnetization M vs magnetic field H variation it is evident that the coercivity, HC decreases for x = 0.5 compound, hinting the magnetic softening of the HoFeO3 compound. Observed magnetocapacitance could be due to lossy dielectric mechanism in the present compound. Indeed, present results would be helpful in understanding the physics behind rare- earth orthoferrites.