Crystal structure and IR spectra of Sr1−xLaxFe1−xCdxO3−δ

Sr1−xLaxFe1−xCdxO3−δ solid solutions with x = 0.1 and 0.5 prepared at 1270 K are shown to have a cubic perovskite structure and the SrLaFeO4 structure, respectively. In the range x = 0.25-0.4, the samples consist of a perovskite phase and SrLaFeO4. As x increases from 0.2 to 0.5, the content of the perovskite phase gradually decreases, and that of the phase isostructural with SrLaFeO4 increases. The IR spectra of the samples with x = 0.3−0.5 are similar to the spectrum of SrLaFeO4. The Sr2/3La1/3FeO3−δ ferrite has the perovskite structure, rather than the Sr2LaFe3O8 structure. The synthesis of this ferrite proceeds through the formation of SrFeO3−δ and LaFeO3, followed by the mutual dissolution of these orthoferrites.