Single-Molecule Magnets: Ligand-Induced Core Distortion and Multiple Jahn-Teller Isomerism in [Mn12O12(O2CMe)8(O2PPh2)8(H2O)4]

The Mn12Ac single-molecule magnet has been converted for the first time into a form that contains non-carboxylate ligands. Reaction of Mn12Ac with diphenylphosphinic acid converts it into the title compound in which eight of the acetate (Ac) groups have been replaced with Ph2PO2 (P) groups. The Mn12AcP product retains the S=10 ground state and single-molecule magnetism properties of Mn12Ac, and displays hysteresis loops containing steps due to quantum tunneling of the magnetization. The crystal structures show that Mn12AcP can exist in three Jahn-Teller isomeric forms differing in the relative arrangement of the Mn(III) Jahn-Teller distortion axes.