The discovery of a new form of pure carbongiant molecules called fullerenes and subsequelltly of a new crystalline form of carbon -fullerite crystals has been a full-scale scientific boom over the past few years. Hundreds of laboratories all over the world are being engaged in synthesizing and studying fullerenes and fullerites and their derivatives, the number of publications amounts to two thousand, and the rate and scope of researches goes 011 growing. This report is not a scientific review

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... nd it-is not my aiin to cstablish scientific priorities. This is rather a scientific popular lecture that better fits in with the spirit of this session. In view of this, not to overburden my report, I shall not make individual references in the text and figures since, to be exact and consistent, the number of such references must be very large. At the end of rliy lecture I shall give references t o several recent very good reviews devoted to individt~al problenis of fullerene pliysics and chemistry. 'l'he reatlei. will find tile necessary ~xhrenccs to originals in these reviews. History The existence of giant niolecules of carbon, boron or silicon llas loi~g I)eeri hypothized. Individual quantum chemical calculations evidenced for thc possibility of stable AGO, and SO on clusters. 1 know about the results of such calculations made and published ill Moscow back in late 60s early 70s. Possibly, there wcrc Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/jp4:1994908 JOURNAL DE PHYSIQUE IV other similar considerations and calculations, however, the ideas and models contained in them were hypothetical and based 011 general though quite sensible, from the stand point of quantum chemistry, assumptions. I t was only in 1985 that Richard Smalley's group at Rice University, Texas in collaboration with Harry ICroto a t the University of Sussex, England, reported the result of their experimental studies that vapors formed upon laser vaporization of graphite contained considerable amounts of carbon clusters CGO, which was recognized mass-spectrometrically. Concurrently, W.Kratschmer from the Max Planck Institute for Nuclear Physics, Heidelberg, Germany ant1 Donaltl I~luffman, University of Arizona, 'l'ucson third type compounds i.e. exohedral ones as well as of the structure of these compounds is, precisely, the province of the fullerene chemistry comprising the main ideas and approaches of organic chemistry. The key moment in the understandi~lg of the fullerene molecule behavior in various chemical reactions is that the occurrence of the double bond in pentagonal ring must be excluded. There is only one way of packing pentagons and hexagons so that a stable isomer could be formed. Some versions are illustrated in fig.17. As contrasted from aromatic molecules, fullerenes d o not possess atoms of hydrogen or other adtled groups, --therefore, they are not capable of substitution reiction. Substitution reactions can takc place only with derivatives, especially those formed by addition. 'l'he electronic structure of fullerenes molecules suggests that they ought to have an increased electron attracting. 'l'his governs their chemical behavior, for example, they readily react with nucleophiles. At a slow crystallization from benzene CsO fullerene molecules yield solvates, (C6116)4C60 in which spinning of the molecules is so slow that it is possible, using x-ray diffraction method, t o define the structure of the single crystals. The same results are obtained at crystallization from cyclohexanc. 'I'liere are some other complexes from which co-crystallization villi benzene occurs. All these materials obtained a t co-crystallization exhibit so-called host-cluest structures, an example of which with ferrocene is shown in fig.18 . l~lerc is much in colnnion with intercalated compounds when structural stabilization occurs due weak interaction related to charge transfer. Analogous structurs are obtained at the interaction with s~~l p l i~i r (CG0S1 (j and C70S48). These are formed of S8 rings. As for remaining typical chemical reactions of fullerenes, known by the present time, I shall restrict myself to their brief listing. Anion formation and oxidizing processes These processes are of clear electrochemical nature. In process is rather typical for organic chemistry and it is being intensively studied using platinum asacalalyst. The interaction of C60 with t-butyl-lithium belongs to the same class of reactions. Details of such reactions are rather complicated. Addition reactions These reactions can be categorized into three groups: 2) Additions i~ivolving bridging , 3) Additions of separate groups , Category 2 comprises reactions with the formation of epoxides from isolated C60 These are oxygen bridges. Addition of methylene to CGO and CTO goes via tlie forniation of' car1)on bridged. There are recent reports on synthesis of niethanofullerenes. In reactions will) metals than as aromatics. Among reactions of addition of individual groups one riiay distinguish addition of halogens and hydrogen. Only 24 groups can be atldecl to C 60 so that two of them were not neighbours ( fig.19 ). Specific structure of CGOBr(; is shown in fig.20 . Polymerization Polymers comprising C60 may be confincd to three types: CM'O of t l i~~i i ilre the pearl necklace type, fig.21 , tlie third type is pendant chain, fig.21 . Onc niay assume that their two-and threedimensional versions may be describetl as a polymer net work or lattice. Probably, the third type having a direct 1)ond between tlie cagcs C9-62 JOURNAL DE PHYSIQUE IV forms at polymerization of CGO under the ultra-violet irradiation in the absence of oxygen. In conclusion of this section I give the general scheme of all chemical reaction involving fullerenes ( fig.22 ). Conclusion It is clear that besides a great scientific interest investigations of fullerenes promise considerable practical implementation. In addition t o what has been already mentioned, they can be used in solid state quantum electronics, optics and in production of electric batteries. Many opportunities for chcmical technology and chcrnical analyt~cal ~llcthods are in sight.