CHARGE DISPROPORTIONATION IN Fe4+-OXIDES WITH PEROVSKITE-TYPE STRUCTURES
نویسندگان
چکیده
For a further examination and elaboration of our simple charge disproportionation model for Fe4+-oxides, 2~e" + Fe3+ + Fe5+, two series of solid solutions Cal-xSrxFe03 and Srl-xLaxFe03 with the perovskite structure have been studied. The Msssbauer spectrum of Sro.sLao.sFeO3 at 4 K clearly indicates the disproportionation. For both series of oxides, the disproportionation seems to set in at the TN1s.
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