Molecular oxygen generation from the reaction of water cations with oxygen atoms

Ryan C Fortenberry; Tarek Trabelsi; Brent R Westbrook; Weston A Del Rio; Joseph S Francisco

doi:10.1063/1.5102073

Molecular oxygen generation from the reaction of water cations with oxygen atoms

J Chem Phys. 2019 May 28;150(20):201103. doi: 10.1063/1.5102073.

Authors

Ryan C Fortenberry¹, Tarek Trabelsi², Brent R Westbrook³, Weston A Del Rio¹, Joseph S Francisco²

Affiliations

¹ Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677-1848, USA.
² Department of Earth and Environmental Science Philadelphia, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
³ Department of Chemistry, St. Edward's University, Austin, Texas 78704, USA.

PMID: 31153175
DOI: 10.1063/1.5102073

Abstract

The oxywater cation (H₂OO⁺), previously shown to form barrierlessly in the gas phase from water cations and atomic oxygen, is proposed here potentially to possess a ²A″ ←⁴A″ excitation leading to the H₂⋯O₂ ⁺ complex. This complex could then easily decompose into molecular hydrogen and the molecular oxygen cation. The present quantum chemical study shows that the necessary electronic transition takes place in the range of 1.92 eV (645 nm), in the orange-red range of the visible and solar spectrum, and dissociation of the complex only requires 5.8 kcal/mol (0.25 eV). Such a process for the abiotic, gas phase formation of O₂ would only need to be photocatalyzed by visible wavelength photons. Hence, such a process could produce O₂ at the mesosphere/stratosphere boundary as climate change is driving more water into the upper atmosphere, in the comet 67P/Churyumov-Gerasimenko where surprisingly high levels of O₂ have been observed, or at gas-surface (ice) interfaces.