The Counterintuitive Relationship between Orbital Energy, Orbital Overlap, and Bond Covalency in CeF62– and CeCl62–

The 4f orbitals of Ce(IV) have shown appreciably enhanced covalent mixing with ligand orbitals relative to those of Ce(III). Here, X-ray spectroscopy, magnetic susceptibility measurements, and theoretical methods are used to investigate 4f covalency in CeF