Japanese Journal of Applied Physics · 1977 · 15 citations · 0 references
Natural SciencesChemistryPhysicsCrystal StructureInorganic ChemistrySpectroscopyCoordination ChemistryInorganic SpectroscopyMolecular Orbital TheoryTransition Metal ComplexesX-ray CrystallographyX-ray SpectroscopyElectronic Structure AnalysisElectronic Structure Of Metal ComplexesHigh-resolution X-ray SpectroscopyHybridization TheoryMolecular Orbital AnalysisOctahedral ComplexesX-ray Absorption Near Edge StructureX-ray Absorption Spectroscopy
The X-Pay Co K absorption edge structures of octahedrally coordinated [Co(CN)6]3- and [Co(NO2)6]3-, and tetrahedrally coordinated [Co(NCS)4]2- are accurately measured with a high-resolution two-crystal spectrometer. These three complex ions each have peculiarly low energy absorption in the main absorption edges contrary to Mitchell-Beeman's idea based on Pauling's hybridization theory. The molecular orbital theory provides a qualitative interpretation suitable for these low energy absorptions. In [Co(CN)6]3- and [Co(NO2)6]3- low energy absorption may be principally attributed to the transition of the Co Is electron into the 4t1u antibonding orbital constructed mainly from the antibonding π* orbitals of ligands. In [Co(NCS)4]2- it may be ascribed to Co 1s–2a1 transition.