An unstable intermediate has been detected and isolated in the reaction of ozone with C60 in solution. On the basis of its UV−vis absorption spectrum, the measured release of O2 in its decay to the epoxide C60O, and the first-order kinetics of this reaction, the intermediate has been identified as C60O3, a primary ozonide. This [6,6]-closed adduct of ozone with C60 thermally dissociates to C60O plus O2 in toluene solution, octane solution, and the solid phase with rate constants (at 23 °C) of 4.6 × 10-2, 1.3 × 10-3, and 3.0 × 10-3 min-1, respectively. The activation energy for dissociation in toluene solution is approximately 89 kJ mol-1. Semiempirical quantum calculations indicate that the formation and subsequent dissociation of C60O3 are both exothermic processes. These findings constitute the first observation of a fullerene ozonide.

Carbon in the petrologic matrices of a number of ordinary chondrites of groups €3, L, and LL, and of types 3 through 6 was studied with a nuclear microprobe and a Raman microprobe. The majority of the matrices had carbon contents in the narrow range between 0.03 and 0.2 wt%. The carbon content decreased only slightly with increasing petrologic type. Carbonrich coats around troilite and/or metal phases occured in five meteorites. Poorly ordered carbon was found in the matrices. The carbon in the meteorites of higher petrologic types was slightly better ordered than in the meteorites of lower types. The narrow range of carbon contents and the similarity of the structural form of carbon in the matrices of the measured ordinary chondrites, which represent all groups and types, imply that their matrices may contain a common component, which might be of interstellar origin.

Abstract-High-resolution transmission electron microscopy micrographs of acid-resistant residues of the Allende, Leoville, and Vigarano meteorites show a great variety of carbon structures: curved and frequently twisted and intertwined graphene sheets, abundant carbon black-like particles, and hollow "sacs". It is suggested that perhaps all of these are carriers for the planetary Q-noble gases in these meteorites. Most of these materials are pyrocarbons that probably formed by the pyrolysis of hydrocarbons either in a gas phase, or on hot surfaces of minerals. An attempt was made to analyze for argon with particle-induced x-ray emission in 143 spots of grains of floating and suspended matter from freeze-dry cycles of an Allende bulk sample in water, and floating "black balls" fiom sonication in water of samples fiom the Allende meteorite. The chemical compositions of these particles were obtained, but x-ray signals at the wavelength of argon were obtained on only a few spots.-

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