METASTABLE DISSOCIATION OF METALLOCARBOHEDRENES - REACTION CHANNELS AND CLUSTER STABILITIES

An investigation of the metastable unimolecular dissociation channels and decay fractions of Ti(m)C(n)+ was made using a reflectron time-of- flight mass spectrometer, coupled with a laser vaporization source in conjunction with multiphoton ionization. The measurements of the decay fractions show that Ti8C12+ is a very stable species in accordance wi th expectation for a closed cagelike structure and, most importantly, provide the first available data on the relative stabilities for diffe rent cluster ions involved in the formation of metallocarbohedrenes (M et-Cars). Furthermore, the results reveal that the Ti8Cn+ mainly lose carbon species for n greater-than-or-equal-to 14, while TimC12+ loses only Ti for m greater-than-or-equal-to 6 and both Ti and C3 for m = 4 and 5; C2 is never a product of decomposition for this range of Met-Ca r related species. The present findings are valuable in providing qual itative information for assessing theoretical calculations of structur es and properties of metallocarbohedrenes and their building blocks.