New molecular complexes of fullerenes C-60 and C-70 with tetraphenylporphyrins M(tpp), in which M = H-2, Mn, Co, Cu, Zn, and FeCl.

Abstract

New molecular complexes of fullerenes C-60 and C-70 with tetraphenyl-porphyrins [M(tpp)] in which M = H-2, Mn-II, Co-II, Cu-II, Zn-II and (FeCl)-Cl-III, have been synthesised. Crystal structures of two C-60 complexes with H2TPP, which differ only in the number of benzene solvated molecules, and C-60 and C-70 complexes with [Cu(tpp)] have been studied. The fullerene molecules form a honeycomb motif in H2TPP . 2C(60). 3C(6)H(6), puckcred graphite-like layers in H2TPP . 2C(60). 4C(6)H(6), zigzag chains in [Cu(tpp)].C-70.1.5C(7)H(8).0.5C(2)HCl(3) and columns in [Cu(tpp)](2).C-60. H2TPP has van der Waals contacts with C-60 through nitrogen atoms and phenyl groups. Copper atoms of the [Cu(tpp)l molecules are weakly coordinated with C- 70, but form no shortened contacts with C-60. The formation of molecular complexes with fullerenes affects the ESR spectra of [M(tpp)] (M = Mn, Co and Cu). [Mn(tpp)] in the complex with C- 70 lowers its spin state from S = 5/2 to S = 1/2, whereas [Co(tpp)] and [Cu(tpp)] change the constants of hyperfine interaction. ESR, IR, UV-visible and X-ray photoelectron spectroscopic data show no noticeable charge transfer from the porphyrinate to the fullerene molecules.