Gas-Phase Chemistry of Vanadium Oxide Cluster Cations. 1. Reactions with C2F6 and CH3CF3

The reactivities of mass-selected vanadium oxide cluster cations with fluorocarbons were studied by using a triple-quadrupole mass spectrometer coupled with a laser vaporization source. The vanadium oxide species V 2 O 4 - 7 +, V 3 O 6 - 9 +, V 4 O 8 - 11 +, V 5 O 11 - 13 +, V 6 O 13 - 16 +, and V 7 O 16 - 18 + displayed unique reactivities with CH 3 CF 3 and C 2 F 6 . Among the reaction pathways observed were association, HF elimination, cracking of the carbon−carbon bond, and fluorine abstraction with oxygen transfer from the cluster to the neutral reactant molecule. Interestingly, the reactions differed for clusters within the same series and also from series to series. For example, the reaction of V 2 O 4 + with CH 3 CF 3 produces the HF-elimination product V 2 O 4 ·HF + . However, the cluster V 2 O 5 + reacts with CH 3 CF 3 to produce the cracking product V 2 O 5 ·CF 3 + but also reacts to abstract 2 fluorine atoms with transfer of an oxygen atom to the neutral reactant molecule. The reaction of these 2 clusters with C 2 F 6 generates only association products.