The Magnetic Properties for Europium-Doped BiFeO3

The crystallographic and magnetic properties of europium-doped Bi1−xEuxFeO3 prepared by a sol-gel method have been studied by X-ray diffraction, superconducting quantum interference device (SQUID) magnetometer, vibrating sample magnetometer (VSM) and Mössbauer spectroscopy. The X-ray diffraction pattern for Bi0.9Eu0.1FeO3 was analyzed by the Rietveld refinement using FULLPROF computer program. The crystals were determined to be a rhombohedrally distorted perovskite-like structure with a space group of R3c. SQUID and VSM measurements showed the antiferromagnetic behavior with Néel temperature (TN) of 638 and 633 K for x=0.1 and 0.2, respectively. A least-squares fitting program was used to determine the Mössbauer parameters by assuming Lorentzian line shapes. The valence state of Fe ion is Fe3+ relative to the Fe metal, according to the isomer shift (δ) value = 0.39 mm/s at 4.2 K. In determining the inter-atomic binding force in Bi0.9Eu0.1FeO3, the Debye temperature was 486 and 477 K, respectively.