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Reaction of an excess of iodine monochloride with Cm, in either benzene or toluene at room temperature, gives a quantitative yield of CgoCls, the 13C NMR spectrum of which indicates that it is isostructural with CmBrs.The specific derivatisation of Cm is a key target in the development of its chemistry. Because halogeno compounds are generally important synthons, preparation and characterisation of halogenofullerenes is of particular significance.

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We present first-and second-order Raman spectra of boron-doped multiwalled carbon nanotubes. The Raman intensities are analyzed as a function of the nominal boron concentration. The intensities of both the D mode and the high-energy mode in the first-order spectra increase with increasing boron concentration, if normalized with respect to a second-order mode. We interpret this result as an indication that the high-energy mode in carbon nanotubes is defect-induced in a similar way as the D mode. Based on this result, we provide a preliminary quantitative relation between the boron concentration and the Raman intensity ratios.

Reaction of c6&& with benzene/FeCI3 yields C60Ph5CI which is readily reduced t o C60Ph5H, the main product of reacting c 6 0 with BrJFeCIdbenzene; both compounds have been characterised by NMR spectroscopy.The sp2-hybridised carbon framework and the associated cage strain makes [60]fullerene a potent electrophile.1 [60]Fullerene appears to be more electrophilic than [70]fullerene, as indicated by the IH resonances in the NMR spectra of hydrogenated [60]fullerenes lying considerably downfield from those for hydrogenated [70]fullerenes2~3 and by the equilibrium constants for reaction of [a]and [70]-fullerenes with N,N-dime t hylaniline .4We showed previously that C60Ph12 was amongst the products obtained in electrophilic substitution of benzene by [60]fullerene in the presence of Br2/FeC13.5 Friedel-Crafts reaction of polychlorinated [60]fullerenes with benzene gave products containing up to 22 phenyl groups.6 We have now isolated some 10 products (some as yet uncharacterised) from the former reaction, find that the main product is CmPhSH, and that this is also formed by reacting CmCl6 (which we described recently)7 with benzene/FeC13 followed by reduction.CmPh5C1 was prepared by heating CmCl67 with benzene-FeCI3 for 20 min, cooling, washing the benzene layer with water, separating and drying (MgS04). The residue obtained after benzene removal was set aside to crystallise from carbon tetrachloride, and gave translucent orange crystals (68%). These crystals contain CC14 trapped in the lattice, for on heating to ca. 80 "C they become opaque, the loss of CC14 was also monitored by IR spectroscopy. The mass spectrum (Fig. 1, EI, heated DCI probe), the first obtained for a chlorinated fullerene, confirmed the molecular formula as CmPh5C1. The

Atomic resolution images of multiwalled boron nitride nanotubes have been obtained using scanning tunneling microscopy operating at tunneling currents below 20 pA and biases of approximately −2.5 V. Lattice images acquired with negative sample biases exhibit trigonal symmetry that is interpreted as resulting from nitrogen states. Tunneling spectroscopy confirms band gaps between 4.5 eV and 4.8 eV for tube diameters above 5 nm. Tunneling barrier height measurements made using standard current–distance analysis yields Φ∼6.3±0.7 eV for the boron nitride nanotubes.

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