| Abstract
| - Reactions of neutral vanadium oxide clusters with small hydrocarbons, namely C2H6, C2H4, andC2H2, are investigated by experiment and density functional theory (DFT) calculations. Single photonionization through extreme ultraviolet (EUV, 46.9 nm, 26.5 eV) and vacuum ultraviolet (VUV, 118 nm, 10.5eV) lasers is used to detect neutral cluster distributions and reaction products. The most stable vanadiumoxide clusters VO2, V2O5, V3O7, V4O10, etc. tend to associate with C2H4 generating products VmOnC2H4.Oxygen-rich clusters VO3(V2O5)n=0,1,2..., (e.g., VO3, V3O8, and V5O13) react with C2H4 molecules to causea cleavage of the CC bond of C2H4 to produce (V2O5)nVO2CH2 clusters. For the reactions of vanadiumoxide clusters (VmOn) with C2H2 molecules, VmOnC2H2 are assigned as the major products of the associationreactions. Additionally, a dehydration reaction for VO3 + C2H2 to produce VO2C2 is also identified. C2H6molecules are quite stable toward reaction with neutral vanadium oxide clusters. Density functional theorycalculations are employed to investigate association reactions for V2O5 + C2Hx. The observed relativereactivity of C2 hydrocarbons toward neutral vanadium oxide clusters is well interpreted by using the DFTcalculated binding energies. DFT calculations of the pathways for VO3+C2H4 and VO3+C2H2 reactionsystems indicate that the reactions VO3+C2H4 → VO2CH2 + H2CO and VO3+C2H2 → VO2C2 + H2O arethermodynamically favorable and overall barrierless at room temperature, in good agreement with theexperimental observations.
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