Study of local distortion and spin reorientation in polycrystalline Mn doped [formula omitted].

The present work reports preparation of polycrystalline G d F e 1 − x M n x O 3 (x = 0.0 to 0.5) samples with solid-state reaction method and characterization using x-ray diffraction, 57 Fe Mössbauer spectroscopy, magnetization measurements, leakage current density and soft x-ray absorption spectroscopy measurements. Although F e 3 + and M n 3 + have similar ionic radii, noticeable variations in lattice parameters are seen which are attributed to local distortions introduced by Jahn-Teller active M n 3 + doping. Antiferromagnetic transition temperature corresponding to F e 3 + ordering ( T N , F e ) and G d 3 + ordering ( T N , G d ) is found to decrease with Mn doping, which could be due to weakening of Fe-Fe interaction and Gd-Gd interactions respectively. The Mn substitution at Fe site in G d F e O 3 is found to induce F e 3 + spin reorientation transition ( T S R T ) at a critical concentration and T S R T is found to increase with the Mn doping. Temperature dependent 57 Fe Mössbauer measurements have been carried out to study the local distortions by estimating quadrupole shift, the evolution of magnetism and also the spin reorientation transition in G d F e O 3 with Mn doping. Leakage current density is found to increase with Mn doping in G d F e O 3 , initially very fast and almost saturating for higher concentrations of Mn doping due to the formation of multiple oxidation states of dopant Mn at lower concentrations as evidenced from soft x-ray absorption spectroscopy measurements. [ABSTRACT FROM AUTHOR]