Why Are There No Terminal Oxo Complexes of the Late Transition Metals? or The Importance of Metal–Ligand π Antibonding Interactions

Abstract π antibonding interactions result from the overlap of a filled π symmetry ligand orbital with a filled metal d orbital. This antibonding plays an important role in the chemistry of π donor ligands such as oxo and alkoxide. It is in large part responsible for the lack of late transition metal complexes with terminal oxo ligands, and can explain some of the unusual chemistry of late metal alkoxide complexes.