Mixed Valences Due to Anion Deficiencies

The change of composition of an ideal ABO3 perovskite may lead to different oxidation states of cations, which in turn would lead to different geometry of the lattice, which finally may affect the surface and catalytic properties. Such an 

The SrFeO , compounds are examples of defect perovsldtes and their chemistry can be described according to the homologous series A B 03 i (n = 2 to 00). Similar structures with ordered vacancies are the perovskites Ca2Mn20s and 

The crystal field environment of iron switches from octahedral to square pyramid in both cases during reduction and vice versa dimng reoxidation. As 

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