EFFECT OF Mn DOPING ON STRUCTURAL AND DIELECTRIC PROPERTIES OF GdFeO3.

We have synthesized GdFe1-xMnxO3 (x=0.0, 0.1, 0.2 and 0.3) by solid state reaction route in order to understand their structural and dielectric properties. X-ray diffraction (XRD) patterns confirm single phase nature and the orthorhombic crystal symmetry of our samples. The lattice parameters are determined from the PowderX software, and are found to decrease with increase in Mn concentration. The most intense peak shifts towards lower 2? values with increase in Mn concentration indicating the development of strain in the crystal structure. Williamson-Hall-plots of GdFe1-xMnxO3(GFMO) are used to investigate physical parameters such as strain, stress, and energy density using different models namely, uniform deformation model (UDM), uniform deformation stress model (UDSM) and uniform deformation energy density model (UDEDM). The strain, stress, energy density and crystallite size increase as the concentration of Mn increases. The value of dielectric constant (?') is found to decrease with the increase in frequency while it enhanced with increase in Mn concentration. The log (f × ?') versus log (f) graphs have been plotted to verify the universal dielectric response (UDR) behavior. All the samples follow UDR model almost in the whole range of measured frequencies.