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Gil, D. M., M. C. Navarro, M. C. Lagarrigue, J. Guimpel, R. E. Carbonio, and M. I. Gómez. "Synthesis and structural characterization of perovskite YFeO3 by thermal decomposition of a cyano complex precursor, Y[Fe(CN)6]Â·4H2O}." Journal of Thermal Analysis and Calorimetry (2010): 1–8.
Abstract: The thermal decomposition of Y[Fe(CN)6]Â·4H2O has been studied in order to investigate the formation of the multi-ferroic oxide YFeO3. The starting material (Y[Fe(CN)6]Â·4H2O) and the decomposition products were characterized by IR spectroscopy, thermal analysis, X-ray powder diffraction (PXRD), and scanning electron microscopy. Metastable YFeO3 with hexagonal structure, space group P63/mmc, was obtained by thermal decomposition of Y[Fe(CN)6]Â·4H2O at 600 Â°C in air. Orthorhombic YFeO3 was obtained by the same method at T â‰¥ 800 Â°C in air. The crystal structure of orthorhombic YFeO3 was refined by Rietveld analysis using PXRD data. We found that it was slightly deficient in Y3+, which is in agreement with the small amount of Y2O3 found as impurity in the sample. The formula of the orthorhombic phase is Y0.986FeO3
Gil, D. M., M. C. Navarro, M. C. Lagarrigue, J. Guimpel, R. E. Carbonio, and M. I. Gómez. "Crystal structure refinement, spectroscopic study and magnetic properties of yttrium hexacyanoferrate (III)." Journal of Molecular Structure 1003, no. 1-3 (2011): 129–133.
Abstract: Y[Fe(CN)6]Â·4H2O has been synthesized and characterized. The crystal structure was refined by Rietveld analysis using X-ray powder diffraction data. Y[Fe(CN)6]Â·4H2O crystallizes in the orthorhombic crystal system, space group Cmcm. Y3+ ion is eight-coordinated forming a bicapped distorted trigonal prism YN6O2. Fe3+ ion is six-coordinated in the form of an irregular octahedra FeC6 group and cyanide linkages between YN6O2 and FeC6 groups build an infinite polymeric array. The vibrational spectrum shows two bands corresponding to antisymmetric and symmetric stretching 12C14N in the CN stretching region. These bands are accompanied by four weak isotopic bands at lower frequency due to the presence of 13C and 15N in relative natural abundance. The HOH bending band split into three bands around 1600Â cmâˆ’1 due to the presence of two kinds of water molecules in the structure. The thermal decomposition has been followed by thermogravimetric and differential thermal analysis, IR spectroscopy and powder XRD. The size and morphology of the complex and its thermal decomposition products were evaluated by scanning electron microscopy. The magnetic measurements confirm that Y[Fe(CN)6]Â·4H2O shows an antiferromagnetic order at low temperatures.
Keywords: Hexacyanoferrate (III); Powder X-ray diffraction; Rietveld analysis; Infrared spectroscopy; Thermal analysis