Electrochemical oxidation of (5, IO, I5,20-tetramethylporphyrinato)copper(II), Cu(tmp), in the presence of the perrhenate ion affords the new molecular conductor [Cu(tmp)12 [Re04]. The compound is composed of partially oxidized Cu(tmp) cations stacked metal-over-metal and surrounded by chains of Reo, anions. Single-crystal, room-temperature conductivity along the needle (crystallographic c) axis averages 40 Q-' cm-I, lower than the values previously reported for Ni(tmp)-based conductors. The conductivity is thermally activated and may be fit to an expression that describes a semiconductor with temperature-dependent carrier mobility: u = a , , F exp(-AE/kBr) (AE = 0.126 (2) eV, a = 3.8 (2)). Magnetic studies show that the local Cu(l1) moments and thc itincrant T-carrier electrons participate in strong spin exchange. This intramolecular Cu-T coupling is shown to mediate Cu-Cu spin cxchange along the linear chains of Cu(l1) ions found in this compound. These magnetic interactions depend on the thermally activated carrier concentration. The angular variation of the line width indicates that exchange is highly one-dimensional. Thc compound crystallizes in space group C&-P4/n of the tetragonal system with two formula units in a cell of dimensions a = 16.774 (9) 8, and c = 6.746 (4) 8, ( V = 1898 A3) at 1 I O K. Full-matrix least-squares refinement of 144 variables gives a final valuc of 0.069 for the R index on for 4695 unique observations and a value of 0.043 for the R index on F for the 2582 observations having Fo2 > 3u(F:).
IntroductionPartial oxidation of metalloporphyrins yields a variety of electronically conductive solids.'-I2 Many of these exhibit the same basic structural motif chains of anions surrounding metal-over-metal stacks of metal lo macro cycle^.^^ One such conductor may be prepared by chemical oxidation of Ni(pc) (pc = phthalocyaninato) with molecular iodine and has the composition Ni(pc)l.' The phthalocyaninato ligand is partially oxidized in this compound, and the iodine is present as linear chains of 1,anions. Ni(pc)I is a highly conductive molecular metal (uRT = (a) Schramm, C. J.; Scaringe, R. P.: Stojakovic, D. R.; Hoffman, B. M.; Ibers, J. A.; Marks, T. J. J. Am. Chem. Soc. 1980,102,6702-6713. (b) Martinsen. J.; Greene, R. L.; Palmer, S. M.; Hoffman, B. M.; Ibers, J. A. J . Am. Chem. SOC. 1983, 105, 677-678. (c) Martinsen, J.; Palmer, S. M.; Tanaka, J.; Greene, R. L.; Hoffman, B. M. Phys. Reo. B 1984, (a) Ogawa, M. Y.; Martinsen, J.; Palmer, S. M.: Stanton, J. L.: Tanaka, J.; Greene, R. L.: Hoffman, B. M.; Ibers, J. A. J. Am. Chem. Sot. 1987, 109, 1 1 15-1 121. (b) Ogawa, M. Y.; Hoffman, B. M.: Lee, S.: Yudkowsky. M.: Halperin, W. P. Phys. Rev. Lett. 1986, 57, 1177-1180. Tatbp = triazatetrabenzoporphyrinato dianion. (a) Liou, K. K.; Ogawa, M. Y.: Newcomb, T. P.; Quirion, G.; Lee, M.; Poirier, M.: Halperin, W. P.; Hoffman, B. M.; Ibers, J. A. Inorg. Chem. 1989,28,3889-3896. (b) Quirion, G.; Poirier, M.; Ogawa, M. Y.: Hoffman, B. M. Solid State Commun. 1987,64,613-616. ( e ) Quirion, G.; Poirier...