A NOVEL TRINUCLEAR COBALT COMPLEX - CRYSTAL AND ELECTRONIC-STRUCTURE OF (PER)4[CO(MNT)2]3

Single crystals of (Per)4[Co(mnt)2]3 (Per = perylene; mnt = maleonitri ledithiolate) were obtained as a minor product of the electrochemical oxidation of perylene and [(n-C4H9)4N][Co(mnt)2]. The structure, solve d by X-ray diffraction at room temperature, was monoclinic, space grou p P2(1)/n with cell parameters a = 12.093(l) angstrom, b = 20.912(1) a ngstrom, c = 16.633(l) angstrom, beta = 94.290(6)-degrees, V = 4194.5( 5) angstrom3, and Z = 2. The crystal structure consists of [Co(mnt)2]3 units and trimers of perylene units with an extra perylene molecule p laced perpendicular to this trimer. The EPR spectrum at room temperatu re shows a narrow (0.4 G) and almost isotropic line at g = 2.0031 ascr ibed to (Per)3+. Extended Huckel molecular orbital calculations on thi s structure support a description of this solid as [CO(Mnt)2]3-(Per)3(Per)0.