New molecular complexes of fullerenes C60 and C70 with tetraphenylporphyrins [M(tpp)] in which M-H2, MnII, CoII, CuII, ZnII and Fe(III)Cl, have been synthesised. Crystal structures of two C60 complexes with H2TPP, which differ only in the number of benzene solvated molecules, and C60 and C70 complexes with [Cu(tpp)] have been studied. The fullerene molecules form a honeycomb motif in H2TPP.2C60. 3C6H6, puckered graphite-like layers in H2TPP.2C60.4C6H6, zigzag chains in [Cu(tpp)].C70.1.5C7H8.0.5C2HCl3 and columns in [Cu(tpp)]2.C60. H2TPP has van der Waals contacts with C60 through nitrogen atoms and phenyl groups. Copper atoms of the [Cu(tpp)] molecules are weakly coordinated with C70, but form no shortened contacts with C60. 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 C70 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.

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Differential scanning calorimetry, solution calorimetry, and room-temperature single-crystal X-ray diffraction were used to study the thermodynamic and structural properties of a solvated crystal C60·2C6H5Br. In the monoclinic solvate, two orientations of C60 were observed with fractional populations of 0.71 and 0.29. The enthalpy of solution of pure C60 in bromobenzene was determined to be Δsol H[C60(s)] = −11.5 ± 2.0 kJ/mol. The enthalpy of solution of the solvated crystal was Δsol H[C60·2C6H5Br(s)] = +28 ± 1 kJ/mol. The phase diagram of the system C60−C6H5Br for T < 423 K was constructed. It predicts the existence of a maximum in the temperature−solubility relationship for C60 in bromobenzene at 350 K. The activity of bromobenzene vapor over the solvated crystal is predicted to be reduced from its value over the pure liquid by a factor of 3.5.

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The cover picture shows the single‐crystal X‐ray structure for C60F18, the first fully characterized aromatic fullerene, possessing a flat and fully delocalized hexagonal benzenoid ring embedded at the center of the fluorinated crown. The bond lengths in this hexagon are all of equal length (1.372 Å). The un‐addended part of the molecule possesses the normal C60 fullerene structure so that the overall appearance is that of a tortoise shell. C60F18 is potentially an important building block for donor–acceptor derivatives with photovoltaic/photonic applications, combining enhanced cage electron withdrawal, with a vacant area for location of donors. The unique geometry also makes the molecule a hexasubstituted benzene, which may be able to participate in η6 coordination to metallic species. Details on this tortoise molecule are described by Slovokhotov, Boltalina, and Taylor et al. on p. 3273 ff.

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