We have found that metal/fullerene adduct ions of the C60 and C70 fullerenes can be formed with silver, gold, rhodium, and palladium by argonion bombardment of fullerenes deposited on a metal substrate, with the use of a Time-of-Flight Secondary Ion Mass Spectrometer (TOF-SIMS). The bis and tris metal/fullerene adducts formed include: Ag(C60)2+, AgC60C70+, Ag(C70)2+, Ag(C60)3+, Ag(C60)2C70+, AgC60(C70)2+, and Rh(C60)2+. In addition, the monomeric adducts AgC60+, AgC70+, AuC60+, AuC70+, RhC60+, RhC70+, and PdC60+ also have been detected. Samples prepared with a raw soot extract gave higher yields of metal/fullerene adducts in TOF-SIMS than those prepared with purified fullerenes. This result may indicate the presence of a matrix component in the raw soot which enhances the formation of fullerene/metal adducts. Spectra obtained from the raw soot show peaks at every 24 daltons corresponding to even-numbered carbon clusters. These peaks occur as low as 600 daltons (C50) and as high as 3000 (C250).
Paul A. Zimmerman and David M. Hercules, "Formation and Detection of Fullerene Metal Complexes Using Time-of-Flight Secondary Ion Mass Spectrometry," Appl. Spectrosc. 47, 1545-1547 (1993)