A Well-Defined Magnesium Complex of C 70 6 .

Controlling and understanding charge state and metal coordination in carbon nanomaterials is crucial to harnessing their unique properties. Here we describe the synthesis of the well-defined fulleride complex [{( Mes nacnac)Mg} 6 C 70 ], 2, ( Mes nacnac)=HC(MeCNMes) 2 , Mes=2,4,6-Me 3 C 6 H 2 , from the reaction of the β-diketiminate magnesium(I) complex [{( Mes nacnac)Mg} 2 ] with C 70 in aromatic solvents. The molecular structure of complex 2 was determined, providing the first high-quality structural study of a complex with the C 70 6- ion. In combination with solution state NMR spectroscopic and DFT computational studies, the changes in geometry and charge distribution in the various atom and bond types of the fulleride unit were investigated. Additionally, the influence of the ( Mes nacnac)Mg + cations on the global and local fulleride coordination environment was examined.