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The photo-oxidation of n-propyl formate (initiated by chlorine atoms) was studied in the presence of NO2, and the products were identified. The Cl atom attack to the molecule occurs in four sites, leading to the formation of formic acid, carbon dioxide, dicarbonylic products, nitrates, peroxy propionyl nitrate (CH3CH2C(O)OONO2, PPN), and a new peroxynitrate, peroxy formyl propyl nitrate (CH3CH2CH2OC(O)OONO2, PFPN). To characterize bulk quantities of the PFPN, its synthesis was carried out by the photolysis of mixtures of CH3CH2CH2OC(O)H, NO2, Cl2, and O2. After purification, its infrared spectrum and thermal stability were determined. The main infrared absorption bands and their corresponding cross sections are 796, 1219, 1302, 1741, and 1831 cm(-1) (1.16, 3.11, 0.88, 2.42, and 1.34 × 10(-18) cm(2) molec(-1), respectively). Thermal decomposition was studied as a function of pressure from 6.0 to 1000 mbar at 298 K, and the activation energy was determined between 293 and 304 K at total pressures of 9.0 and 1000 mbar (Ea = 98 ± 3 and 110 ± 2 kJ/mol, respectively). The atmospheric thermal lifetimes were obtained from kinetic parameters.

The rate constants for the reaction between chlorine atoms and either 5‐methyl‐2‐hexanol, 2,2‐dimethyl‐3‐hexanol, or 2,4,4‐trimethyl‐1‐pentanol at 298 K were determined using the relative method with 2‐butanol and 1‐pentanol as reference compounds. The values obtained for 5‐methyl‐2‐hexanol, 2,2‐dimethyl‐3‐hexanol, and 2,4,4‐trimethyl‐1‐pentanol (k × 1010 cm3 molec−1 s−1) were, respectively, (2.64 ± 0.5), (2.72 ± 0.5), and (2.50 ± 0.4), in agreement with the values of the rate constants reported in bibliography for similar alcohols and the values estimated by structure activity relationship methods. The photooxidation products of 2,4,4‐trimethyl‐1‐pentanol initiated by chlorine atoms were identified (formaldehyde, 2‐propanone, 2,2‐dimethyl propanal, 4,4,‐dimethyl‐2‐pentanone, and 3,3‐dimethylbutanal), and the reaction mechanism was determined.

The atmospheric degradation of molecules containing the C x F 2x+1 C(O) moiety, such as perfluoroaldehydes C x F 2x+1 C(O)H (x = 2 -4) formed in the degradation of telomeric alcohols, could lead to the formation of perfluoroacyl peroxynitrates C x F 2x+1 C(O)OONO 2 . The thermal decomposition of the C x F 2x+1 C(O)OONO 2 family (x = 2, 3, 4) was investigated by infrared spectroscopy and computational models. Each peroxynitrate synthesis was performed through the photolysis of gas mixtures of the corresponding perfluoroaldehyde, chlorine, nitrogen dioxide, and oxygen. Kinetic analysis for the thermal decomposition of peroxynitrates were performed in the range from 297.0 K to 313.7 K at a total pressure of 1000 mbar and the activation energy was experimentally determined.Experimental data were complemented with theoretical data using Gaussian09 Program Suite. The structures of peroxynitrates were optimized using DFT methods. The activation energies were calculated and investigated taking into account the stereoelectronic effects and by using theoretical calculations as well as NBO analysis. The influence of anomeric interaction over the O-N bond was evaluated for all the molecules.