Band structure calculation and rietveld refinement of nanoscale GdFeO3 with affirmation of Jahn Teller's distortion on electric and magnetic properties

We report the meticulous study of freshly synthesized rare earth element substituted R-FeO3 (R-Gd) orthoferrite via co-precipitation route and subsequent sintering. The R-FeO3 powder sample is characterized by X-ray Diffractometer (XRD) for the investigation of crystal structure and is confirmed as orthorhombic with space group Pbnm structure. Nanoparticle dimension is captured by Scanning Electron microscope (SEM). Magnetic character of the sample is examined using vibrating sample magnetometer (VSM), it discloses a nearly linear magnetisation behaviour (paramagnetic behaviour). Dielectric studies and electric Polarization (PE loop) are investigated. A shift is observed in the dielectric constant epsilon(r) from 250 degrees C to 300 degrees C. The Rietveld refinement of the crystal structure from the powder XRD confirms GdFeO3 is distorted at octahedral site of FeO6. This distortion is ascertained as weak Jahn -Teller's distortion leads to the unsaturated electric polarization. The electronic properties, total and partial density of states of GdFeO3 are studied and calculated using Tight - Binding Linear Muffin-Tin Orbital (TBLMTO) method with the Atomic Sphere Approximation (ASA). The band gap of the GdFeO3 is found to be 0.32 eV. (C) 2018 Elsevier B.V. All rights reserved.