FTIR/smog chamber experiments and ab initio quantum calculations were performed to investigate the atmospheric chemistry of (CF)CFCN, a proposed replacement compound for the industrially important sulfur hexafluoride, SF. The present study determined k(Cl + (CF)CFCN) = (2.33 ± 0.87) × 10, k(OH + (CF)CFCN) = (1.45 ± 0.25) × 10, and k(O + (CF)CFCN) ≤ 6 × 10 cm molecule s, respectively, in 700 Torr of N or air diluent at 296 ± 2 K. The main atmospheric sink for (CF)CFCN was determined to be reaction with OH radicals. Quantum chemistry calculations, supported by experimental evidence, shows that the (CF)CFCN + OH reaction proceeds via OH addition to -C(≡N), followed by O addition to -C(OH)═N·, internal H-shift, and OH regeneration. The sole atmospheric degradation products of (CF)CFCN appear to be NO, COF, and CFC(O)F. The atmospheric lifetime of (CF)CFCN is approximately 22 years. The integrated cross section (650-1500 cm) for (CF)CFCN is (2.22 ± 0.11) × 10 cm molecule cm which results in a radiative efficiency of 0.217 W m ppb. The 100-year Global Warming Potential (GWP) for (CF)CFCN was calculated as 1490, a factor of 15 less than that of SF.

Smog chamber/Fourier transform infrared (FTIR) techniques were used to measure the kinetics of the reaction of n‐CH3(CH2)xCN (x = 0–3) with Cl atoms and OH radicals: k(CH3CN + Cl) = (1.04 ± 0.25) × 10−14, k(CH3CH2CN + Cl) = (9.20 ± 3.95) × 10−13, k(CH3(CH2)2CN + Cl) = (2.03 ± 0.23) × 10−11, k(CH3(CH2)3CN + Cl) = (6.70 ± 0.67) × 10−11, k(CH3CN + OH) = (4.07 ± 1.21) × 10−14, k(CH3CH2CN + OH) = (1.24 ± 0.27) × 10−13, k(CH3(CH2)2CN + OH) = (4.63 ± 0.99) × 10−13, and k(CH3(CH2)3CN + OH) = (1.58 ± 0.38) × 10−12 cm3 molecule−1 s−1 at a total pressure of 700 Torr of air or N2 diluents at 296 ± 2 K. The atmospheric oxidation of alkyl nitriles proceeds through hydrogen abstraction leading to several carbonyl containing primary oxidation products. HC(O)CN, NCC(O)OONO2, ClC(O)OONO2, and HCN were identified as the main oxidation products from CH3CN, whereas CH3CH2CN gives the products HC(O)CN, CH3C(O)CN, NCC(O)OONO2, and HCN. The oxidation of n‐CH3(CH2)xCN (x = 2–3) leads to a range of oxygenated primary products. Based on the measured OH radical rate constants, the atmospheric lifetimes of n‐CH3(CH2)xCN (x = 0–3) were estimated to be 284, 93, 25, and 7 days for x = 0,1, 2, and 3, respectively.

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FTIR/smog chamber experiments and ab initio quantum calculations were performed to investigate the atmospheric chemistry of (CF3)2CFCN, a proposed replacement compound for the industrially important sulfur hexafluoride, SF6. The present study determined k(Cl+(CF3)2CFCN) = (2.33 ± 0.87) × 10–17, k(OH + (CF3)2CFCN) = (1.45 ± 0.25) × 10− 15 and k(O3 + (CF3)2CFCN) ≤  6 × 10− 24 cm3 molecule–1 s–1, respectively. The experiments were performed in 700 Torr of N2 or air diluent at 296 ± 1 K. The main atmospheric sink for (CF3)2CFCN was determined to be the reaction with OH radicals. In assessing the atmospheric impact of (CF3)2CFCN, an infrared spectrum was recorded, and the atmospheric lifetime, the radiative forcing, and the global warming potential (GWP) were calculated. The integrated cross section (650–1500 cm− 1) for (CF3)2CFCN is (2.22 ± 0.11) × 10− 16 cm2 molecule− 1 cm− 1 which results in a radiative efficiency of 0.217 W m− 2 ppb− 1. The 100-year Global Warming Potential (GWP) for (CF3)2CFCN was calculated to be 1490. The climate impact of (CF3)2CFCN is significantly lower than that of SF6. This study provides a comprehensive description of the atmospheric fate of (CF3)2CFCN.