A Binuclear MnIII Complex of a Scorpiand-Like Ligand Displaying a Single Unsupported MnIII–O–MnIII Bridge

The crystal structure of a binuclear MnIII complex of a scorpiand-like ligand (L) displays an unsupported single oxo bridging ligand with a MnIII–O–MnIII angle of 174.7°. Magnetic susceptibility measurements indicate strong antiferromagnetic coupling between the two metal centers. DFT calculations have been carried out to understand the magnetic behavior and to analyze the nature of the observed Jahn–Teller distortion. Paramagnetic 1H NMR has been applied to rationalize the formation and magnetic features of the complexes formed in solution.