Atmospheric chemistry of cyc-CF₂CF₂CF₂CH=CH–: Kinetics, products, and mechanism of gas-phase reaction with OH radicals, and atmospheric implications

The rate constants for the gas-phase reactions of cyc-CF₂CF₂CF₂CH=CH– with OH radicals were determined by a relative rate method between 253 and 328 K. The rate constant k₁ at 298 K was measured to be (1.08 ± 0.04) × 10⁻¹³ cm³ molecule⁻¹ s⁻¹, and the Arrhenius expression was k₁ = (3.72 ± 0.14) × 10⁻¹³ exp [(−370 ± 12)/T]. The atmospheric lifetime of cyc-CF₂CF₂CF₂CH=CH– was calculated to be 107 d. The products and mechanism for the reaction of cyc-CF₂CF₂CF₂CH=CH– with OH radicals were also investigated. CO, CO₂, and COF₂ were identified as the main carbon-containing products following the OH-initiated reaction. Moreover, the radiative efficiency (RE) was determined to be 0.143 W m⁻² ppb⁻¹, and the global warming potentials (GWPs) for 20, 100, and 500 yr were 54, 15, and 4, respectively. The photochemical ozone creation potential of the title compound was estimated to be 1.3.