Physical review. B, Condensed matter · 1993 · 606 citations · 10 references
Natural SciencesMaterials SciencePhysicsInorganic ChemistryMaterials PhysicsSolid-state ChemistryAb Initio MethodsMetal OxidesOptical Properties Of SolidsPerovskite MaterialsTransition Metal ChemistryTransition Metal ComplexesAtomic Number DependenceElectronic Structure AnalysisEnergy Band GapMott TransitionOxide Electronic StructureOxide PerovskitesPerovskite OxidesTransition Metal Oxides
The optical study of trivalent 3d transition-metal-oxide compounds (RM${\mathrm{O}}_{3}$) with the perovskitelike structure has revealed the variation of their electronic structure with the 3d element (M) as well as the A-site rare-earth element (R). The crossover of the gap nature from the Mott type to charge-transfer (CT) type with increasing atomic number of M is observed to occur around M=Cr. The variation of Mott and CT gaps with M species is quantitatively consistent with the tendency expected from an ionic model. However, for the low-energy electronic structures for the narrow-gap (or metallic) compounds (M=Ti,Co,Ni), the effects of the M-3d--O-2p hybridization must be included.
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