A new perfluorinated peroxynitrate, CF3CF2CF2CF2OONO2. Synthesis, characterization and atmospheric implications

- A new perfluoroalkyl peroxynitrate identified.
- Its thermal stability and UV spectra has been studied.
- First principles calculations were used to explore the ground state potential energy surface.
- Comparison with shorter perfluoroalkyl peroxynitrates is presented.
- Its lifetime is in agreement with the expected for similar peroxynitrates.

CF3CF2CF2CF2OONO2 was synthesized from the photolysis of CF3CF2CF2CF2I, in presence of NO2 and O2. Alkyl peroxynitrates (CxF2x+1OONO2) could be formed in the atmospheric degradation of chlorofluorocarbons, hydrofluorocarbons and hydrofluoroethers. We present here the synthesis and characterization (IR and UV absorption cross sections) of CF3CF2CF2CF2OONO2 and its comparison with those corresponding to other perfluoro alkyl peroxynitrates. The thermal stability was studied as a function of total pressure (from 9.0 to 417 mbar) and temperature (from 283 to 293 K) using infrared spectroscopy. Kinetic parameters measured for the thermal dissociation were Ea = (81 ± 4) kJ/mol and A = 4.8 × 1012. DFT calculations at the B3LYP/6-311+G∗ level were used to explore the ground state potential energy surface. Geometrical parameters, conformer populations and vibrational spectra are presented. The calculated activation energy was 81.3 kJ mol−1 in excellent agreement with experimental results. Atmospheric implications are discussed.