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In page Fullerene:

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Fullerenes are components of soot which is produced in particular ways. In the original (and still prevailing) method, a large electric current is passed between two nearby graphite electrodes in an inert atmosphere. The resulting electric arc vaporizes the carbon that condenses into a sooty residue.[1] Alternatively, soot is produced by laser ablation of graphite or pyrolysis of aromatic hydrocarbons.[2][citation needed] Combustion of benzene can also be efficient.[3][4]