Chemical signatures of Buckminsterfullerene, C 60, under chemical ionization conditions

Abstract

Chemical ionization (CI) spectra are reported for the Buckminsterfullerene molecule, C 60, with the CI reagents hydrogen, ammonia, water, hydrogen chloride, methane, ethylene and isobutane. The spectra are characterized by a strong peak for protonated C 60, C 60H +, except with ammonia. The spectra with hydrogen and ammonia are striking in that they show extensive hydrogenation of C ·+ 60 . C 60H + x peaks up to C 60H + 37 are observed in hydrogen, while the ammonia spectrum shows a preference for an odd number of hydrogen atoms below x = 13. The spectra with methane, ethylene and isobutane show complicated patterns of peaks corresponding to the derivatization of C ·+ 60 with nCH x units, where n has values up to n = 32 in the case of methane. Ion/molecule reactions are discussed which may lead to the formation of C 60H +, the further hydrogenation of this ion, and the derivatization of C ·+ 60 more generally. The results in general indicate a remarkable ability for C 60 to become hydrogenated and derivatized under CI conditions.