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Smog chamber/FTIR techniques were used to investigate the kinetics and mechanism of the Cl atom and OH radical initiated oxidation of 2,2-dichloroethanol at (296 ± 1) K. Relative rate methods were used to measure k(Cl + CHCl2CH2OH) = (5.87 ± 0.96) × 10-12 and k(OH + CHCl2CH2OH) = (5.54 ± 1.94) × 10-13 cm3 molecule-1 s-1. Chlorine atom initiated oxidation of CHCl2CH2OH in one atmosphere of air gives HCOCl, CHCl2CHO, and COCl2 in yields of (62 ± 5)%, (39 ± 10)%, and (8 ± 2)%, respectively. The rate constant k(Cl + CHCl2CHO) = (8.3 ± 16) × 10-12 cm3 molecule-1 s-1 was determined and the IR spectra of CHCl2CHO is reported for the first time. The atmospheric lifetime for CHCl2CH2OH is estimated as 21 days. The experimental results are discussed in the context of the atmospheric chemistry of chlorinated alcohols.

An investigation of CCl3COCl was conducted with the purpose of using the compound as an alternative Cl atom precursor in laboratory settings. CCl3COCl can be used with or without O2 as a source of Cl atoms and photolysis studies in air and N2 diluent displayed COCl2 and CO as being the major photolysis products. Relative rate studies were performed to determine the Cl atom rate coefficients for reaction with CH3Cl and C2H2 and the results were in agreement with literature values. Cl atom rate coefficients for reaction with n-CH2CH(CH2)3CN and n-CH2CH(CH2)4CN were determined as (2.95 ± 0.58) × 10−10 and (3.73 ± 0.60) × 10−10 cm3 molecule−1 s−1, respectively. CCl3COCl requires UV-C irradiation, so not all molecules are feasible for use in e.g. relative rate studies. Furthermore, it is recommended to perform experiments with O2 present, as this minimizes IR feature disturbance from product formation.

Fourier transform infrared smog chamber techniques were used to study the kinetics and mechanisms of the reactions of Cl atoms and OH radicals with pentafluorophenol (C6F5OH) in 700 Torr total pres...

Smog chamber techniques were used to determine k(CH3OCF2CHCl2 + Cl) = (5.04 ± 0.75) × 10−13, k(CH3OCF2CHCl2 + OH) = (2.18 ± 0.38) × 10−13, and k(CH3OCF2CHCl2 + O3)

An investigation of CCl3COCl was conducted with the purpose of using the compound as an alternative Cl atom precursor in laboratory settings. CCl3COCl can be used with or without O2 as a source of Cl atoms and photolysis studies in air and N2 diluent displayed COCl2 and CO as being the major photolysis products. Relative rate studies were performed to determine the Cl atom rate coefficients for reaction with CH3Cl and C2H2 and the results were in agreement with literature values. Cl atom rate coefficients for reaction with n-CH2[double bond, length as m-dash]CH(CH2)3CN and n-CH2[double bond, length as m-dash]CH(CH2)4CN were determined as (2.95 ± 0.58) × 10-10 and (3.73 ± 0.60) × 10-10 cm3 molecule-1 s-1, respectively. CCl3COCl requires UV-C irradiation, so not all molecules are feasible for use in e.g. relative rate studies. Furthermore, it is recommended to perform experiments with O2 present, as this minimizes IR feature disturbance from product formation.

Smog chamber/Fourier transform infrared (FTIR) techniques were used to measure the kinetics of the reaction of n-CH2═CH(CH2)xCN (x = 0–4) with Cl atoms, OH radicals, and O3: k(CH2═CHCN + Cl) = (1.03 ± 0.13) × 10–10, k(CH2═CHCH2CN + Cl) = (2.02 ± 0.35) × 10–10, k(CH2═CH(CH2)2CN + Cl) = (2.75 ± 0.45) × 10–10, k(CH2═CHCN + OH) = (4.21 ± 0.95) × 10–12, k(CH2═CHCH2CN + OH) = (1.55 ± 0.34) × 10–11, k(CH2═CH(CH2)2CN + OH) = (2.98 ± 0.64) × 10–11, k(CH2═CH(CH2)3CN + OH) = (3.34 ± 0.64) × 10–11, k(CH2═CH(CH2)4CN + OH) = (3.61 ± 0.85) × 10–11, k(CH2═CHCN + O3) = (2.55 ± 0.28) × 10–20, k(CH2═CHCH2CN + O3) = (1.17 ± 0.24) × 10–18, k(CH2═CH(CH2)2CN + O3) = (3.35 ± 0.69) × 10–18, k(CH2═CH(CH2)3CN + O3) = (4.07 ± 0.82) × 10–18, and k(CH2═CH(CH2)4CN + O3) = (7.13 ± 1.49) × 10–18 cm3 molecule–1 s–1 at a total pressure of 700 Torr of air or N2 diluents at 296 ± 2 K. CH2ClC(O)CN, HC(O)CN, HC(O)Cl, HCN, NCC(O)OONO2, and ClC(O)OONO2 were identified as products from the Cl initiated oxidation of CH2═CHCN. The product spectra w...

Long pathlength/FTIR smog chamber techniques were used to determine the Cl atom initiated atmospheric oxidation mechanisms for methoxyflurane (CH3OCF2CHCl2) in 700 Torr of air or O2 diluent at 296 K. The oxidation of CH3OCF2CHCl2 in both air and O2 diluent gave one primary carbonyl-containing product in approximately 100% yield and one secondary bi-carbonyl product in addition to COF2 and COCl2, the latter two both with initial molar yields of 2 ± 1%. A mechanism is proposed for the oxidation of methoxyflurane which explains the observed product distribution. IR spectra for HC(O)OCF2CHCl2 and HC(O)OCF2C(O)Cl are calculated and reported.