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A series of samples of solid solutions in the SrxEu1-xFeO3-y (0.00≤x≤1.00) system has been prepared at 1200℃ under an atmospheric air pressure. The structures of solid solutions are studied by X-ray diffraction, thermal, Mohr salt, and Mossbauer spectroscopic analyses. Their physical properties are also discussed with the electrical conductivities. X-ray diffraction data for the compositions of x = 0.00, 0.25, and 1.00 are assigned to the orthorhombic and the compositions of x = 0.50 and 0.75 to the cubic systems. The lattice volume reduced to cubic cell increases with the x value. The mole ratio of Fe4+ ion in the solid solution or τ value is determined by the Mohr salt titration. Oxygen vacancy or y value is calculated by using the electroneutrality condition, and the nonstoichiometric chemical formulas of the system are formulated from the x, τ, and y values. The mixed valency state of Fe ions, the oxygen coordination, and covalent bond character are discussed with the Mossbauer spectroscopic data. The activation enegy of the electrical conductivities depends on the τ value in the temperature range of -100℃ to 600℃ under the air pressure. The Mossbauer spectrum and electrical conductivity of the solid solutions are discussed with nonstoichiometric chemical compositions.
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