Reactions of tantalum oxide cluster cations with 1-butene, 1,3-butadiene, and benzene

Branching ratios for the reactions of l-butene, 1,3-butadiene, and benzene with stoichiometric tantalum oxide clusters (TaO2-3+, Ta2O4-5+, and Ta3O7-8 +) are reported. The major reaction product for most of the clusters is cra cking of the C2-C3 bond of l-butene and 1,3-butadiene to produce TaxOyC2H4. Additionally, Ta2O4+ was the most reactive cluster toward cracking the C2 -C3 bond of both I-butene and 1,3-butadiene. For a majority of these cluste rs there were additional cracking channels to produce TaxOyCH3+ and TaxOyC3 Hz+, when z = 5-6, which occur under multiple collision conditions for l-bu tene and 1,3-butadiene. Under multiple collision conditions, TaO2+, Ta2O4+, and Ta3O7+ exhibited the reaction channels of TaxOyC5H9+ and TaxOyC6H10+ w hen reacted with I-butene. In reactions with 1,3-butadiene, secondary react ion channels of TaxOyC5H7+ and TaxOyC6H8+ were also observed for TaO2+, Ta2 O4-5+, and Ta3O7+. Additionally, under multiple collision conditions, TaO2 and Ta2O4+ also displayed reaction channels of TaxOyC7H9+ and TaxOyC8H10Reactions of most of the stoichiometric tantalum oxide clusters with benzen e showed a cracking channel forming TaxOyC4H4+ and a dehydration channel to form TaxOy-1C6H4+. The most reactive cluster toward cracking benzene was T a3O8+, and the most reactive cluster toward the dehydration reaction was Ta O2+. Reactions of the aforementioned unsaturated hydrocarbons with oxygen-r ich clusters (TaO4-5+, Ta2O6-7+, and Ta3O9-10+) are also reported. The majo r reaction channel of most of these clusters involves loss of molecular oxy gen to form the smaller, more stable stoichiometric clusters, which then pr oceed to react with or associate the hydrocarbon gas.