Ab Initio Kinetic Insights of Atmospheric Oxidation of Vinyl Fluoride (CH₂CHF) with OH Radicals

In addition to being a precursor for polyvinyl fluoride production, vinyl fluoride (CH2CHF), a volatile hydrofluoroolefin (HFO), is currently used as a replacement for traditional refrigerants to replace harmful chlorofluorocarbons (CFCs) and hydrofluorocarbons (HFCs). Since its release into the atmosphere is inevitable, it is essential to understand the kinetic behaviors of its reaction with OH radicals to evaluate its fate and its environmental impact on the atmosphere. In this study, we carried out the statistical Rice-Ramsperger-Kassel-Marcus (RRKM)-based Master Equation simulations on the potential energy surface explored at the M06-2X/aug-cc-pVTZ level to reveal its chemical conversion for a wide range of conditions (200-2000 K and 0.76-76,000 Torr). Providing simulated results that agree with previous scattered experimental data, the model can be confidently used to gain mechanistic insights, which reveals the dominance of the OH addition over the H abstraction under atmospheric conditions. The subsequent removal mechanism of the hydroxylated adducts is also provided to not only qualify several critical and harmful byproducts but also quantify the competition among the related pathways. Calculated photolytic parameters suggest that two carcinogenic products could accumulate in the atmosphere.