Theoretical Kinetic Study of SF ₆ Decomposition via Reactions With H and OH Radicals

A comprehensive kinetic model for SF 6 decomposition in combustion environments has been hindered by the lack of accurate thermodynamic and kinetic data, particularly for radical‐driven high‐temperature chemistry. This study provides ab initio thermodynamic and kinetic data for SF 6 decomposition via reactions with H and OH radicals, key species in combustion chemistry. The thermodynamic properties of various fluorinated species are provided in NASA polynomial format, allowing direct integration into kinetic simulation packages. Three major reaction pathways are examined using density functional theory (DFT) calculations are as follows: (1) SF n + H → SF n − 1 + HF, (2) SF n + OH → SOF n − 1 + HF, and (3) SOF n + OH → SO 2 F n − 1 + HF. These reactions are key steps in forming major products, such as SO 2 and SO 2 F 2 . Temperature‐dependent rate constants are computed, and the corresponding Arrhenius parameters are determined. The decomposition of SF n species is more strongly promoted by OH radicals than by H radicals. SOF n species, formed from SF n and OH radicals, subsequently react with OH radicals to generate SO 2 and SO 2 F 2 . These findings provide a valuable thermodynamic and kinetic dataset that can be integrated into combustion or pyrolysis kinetic models to develop a detailed SF 6 decomposition model.