GAS-PHASE CHEMISTRY OF VANADIUM-OXIDE CLUSTER CATIONS - 1 - REACTIONSWITH C2F6 AND CH3CF3

The reactivities of mass-selected vanadium oxide cluster cations with fluorocarbons were studied by using a triple-quadrupole mass spectrome ter coupled with a laser vaporization source. The vanadium oxide speci es V2O4-7+, V3O6-9+, V4O8-11+, V5O11-13+, V6O13-16+, and V7O16-18+ dis played unique reactivities with CH3CF3 and C2F6. Among the reaction pa thways observed were association, HF elimination, cracking of the carb on-carbon bond, and fluorine abstraction with oxygen transfer from the cluster to the neutral reactant molecule. Interestingly, the reaction s differed for clusters within the same series and also from series to series. For example, the reaction of V2O4+ with CH3CF3 produces the H F-elimination product V2O4. HF+. However, the cluster V2O5+ reacts wit h CH3CF3 to produce the cracking product V2O5. CF3+ but also reacts to abstract 2 fluorine atoms with transfer of an oxygen atom to the neut ral reactant molecule. The reaction of these 2 clusters with C2F6 gene rates only association products.