study has also revealed some flaws in the previous model of inter-double-helix hydrogen bonding. [1] Imberty, A.; Chanzy, H.; Pérez, S.; Buléon, A.; Tran, V. Functionally substituted fullerene derivatives are of interest since it is possible to obtain both biologically active substances and new materials for nanotechnology on their basis. The spherical platform of fullerene allows one to design molecules with various fragments, which are responsible for the specific properties. At the same time the crystal structure of such compounds is studied insufficiently, that is why Crystallographic Data Bases contain information about not more than 80 fullerene C60 derivatives structures. Interesting feature of these compounds (both derivatives and fullerene complexes) in solid state is their active participation in pi-electronic interactions between each other and with other compounds incorporating aromatic fragments. Owing to these interactions the compounds can form in a crystal the supramolecular structures of various type, that, apparently, finds reflection in their particular properties. Basing on literature structural data for organic derivative of fullerene and on our original X-ray data for the bis-and mono-adducts of the methanofullerenes and pyrrolidino-fullerenes, we have analysed the intermolecular interactions, crystal packing and supramolecular structure of these compounds from the point of view of such interactions. It was found, that in spite of the presence of large substituents in the molecules and solvate molecules in the crystals, which hinder such interactions, the fullerene fragments are closely packed with different fullerene environments-honeycomb structure, zigzag-chain,  dimers, columns and layers, and preferably interact face-to-face with the 5-and 6-membered aromatic rings. The majority of the compounds forms 2D-structures-layers of various topology with fullerenes coordination equal to 3 or 4. Presence of molecules-guests with aromatic fragments or aromatic fragments in the fullerene derivatives leads to their obligatory participation in such interactions and to the destruction of the fullerene-fullerene interactions. Recently we carried out the synthesis of malonate nitroxide metanofullerene, which shows, in combination with known anticancer drug cyclophosphamide, the high antitumor activity against leukemia P-388. It was shown by X-ray single crystal analysis that methanofullerene with two nitroxide groups has a diamond-like environment in the crystal due to fullerene-fullerene interactions [1]. In the same time the first examples of the phosphorylated mono-and bis-methano-fullerenes with large substituents have lower coordination of fragments-zigzag chains and pi-dimers. The comparative analysis of the results for the organic derivatives and for the fullerene C60 inclusion compounds is presented. The topology of the crystals is analysed additionally on the base of proposed model of localization of hydrophilic and hydrophobic regions in the crystals of organic compounds. Keywords: hydrogen...

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After pulsed photoexcitation of a new fullerene-linked bisnitroxide, a well resolved transient EPR spectrum is detected which is assigned to an excited quintet spin state generated by spin coupling of the nitroxides and the fullerene excited triplet.

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The reactions of electrochemical reduction of methanofutlerenes bearing phosphonate and alkoxycarbonyl groups at the exo-carbon atom were studied. The mechanism of the retroBingel reaction as the cleavage ofnvo C--C bonds between the C(611 atom and the tullerene shell accompanied by electrochemical electron transfer was proposed.

We investigated by W-band (94 GHz) transient electron paramagnetic resonance (TREPR) and photoinduced absorption (PIA) spectroscopy two fullerene derivatives bearing a nitroxide radical unit. After pulsed laser photoexcitation of the molecules in liquid toluene solution, complex EPR spectra are recorded, with lines in absorption and emission. The intrinsic higher spectral and temporal resolution of the W-band frequency leads to the assignment of all the lines in the spectrum and the determination of the sign and the absolute value of the exchange coupling between the fullerene in its photoexcited triplet state (S(T) = 1) and the radical (S(R) = 1/2). The two compounds with different fullerene-nitroxide spacers show opposite-ferromagnetic and antiferromagnetic-exchange couplings. The time evolution of the spectra and the polarization of the lines are interpreted in terms of several possible spin polarization mechanisms. The EPR measurements are complemented with PIA experiments.

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