Counter-Intuitive Gas-Phase Reactivities of [V2]+ and [V2O]+ towards CO2 Reduction: Insight from Electronic Structure Calculations

Abstract

[V2O]+ remains “invisible” in the thermal gas-phase reaction of bare [V2]+ with CO2 giving rise to [V2O2]+; this is because the [V2O]+ intermediate is being consumed more than 230 times faster than it is generated. However, the fleeting existence of [V2O]+ and its involvement in the [V2]+ → [V2O2]+ chemistry are demonstrated by a cross-over labeling experiment with a 1:1 mixture of C16O2/C18O2, generating the product ions [V216O2]+, [V216O18O]+, and [V218O2]+ in a 1:2:1 ratio. Density functional theory (DFT) calculations help to understand the remarkable and unexpected reactivity differences of [V2]+ versus [V2O]+ towards CO2.