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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.

The paper presents data on the synthesis, IR, electronic, X-ray photoelectron, and ESR spectroscopies of fullerene C 60 molecular complexes with various types of donor compounds, namely, substituted tetrathiafulvalenes, aromatic hydrocarbons, diazodithiafulvalene, tetraphenyldipyranylidene, tetrasulfur tetranitride, saturated amines, some metallocenes, and Co(II) and Mn(II) tetraphenylporphyrins. Crystal structures of some of these complexes are discussed. The degree of charge transfer in the complexes is evaluated from the shift of the F 1u (4) C 60 mode in the IR spectra. The factors responsible for the appearance of the symmetry-forbidden C 60 vibrations and the splitting of the absorption bands of C 60 in the complexes are considered. The electronic absorption spectra of some complexes show the decrease of the intensity of electron transitions of C 60 at 420±530 nm and the appearance of new absorption bands attributed to charge transfer from the donor to C 60 . The dependences of the energy of charge transfer in the C 60 complexes on ionisation and redox potentials of substituted tetrathiafulvalenes are derived. Peculiarities of donor±acceptor interaction of donor molecules with the spherical C 60 are considered.{Characteristics of C 60 complexes are available as supplementary data.

h i g h l i g h t sUse of metal hydride storage and compression in hydrogen energy storage systems. AB5-and AB2-type hydrides for hydrogen storage and compression applications.Development of the energy storage systems and their metal hydride based components.

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