Taketani, Fumikazu2; Nakayama, Tomoki2; Takahashi, Kenshi2; Matsumi, Yutaka2; Hurley, Michael D.3; Wallington, Timothy J.3; Toft, Anne4; Andersen, Mads Peter Sulbæk6
1 Department of Chemistry, Faculty of Science, Københavns Universitet2 unknown3 Ford Motor Company (Biz)4 Syddansk Universitet5 Administration, Department of Chemistry, Faculty of Science, Københavns Universitet6 Administration, Department of Chemistry, Faculty of Science, Københavns Universitet
kinetics, mechanisms, and products of Cl atom- and OH radical-initiated oxidation in the presence and absence of NO<sub><i>x</i></sub>
Smog chamber/Fourier transform infrared (FTIR) and laser-induced fluorescence (LIF) spectroscopic techniques were used to study the atmospheric degradation of CH3CHF2. The kinetics and products of the Cl(2P(3/2)) (denoted Cl) atom- and the OH radical-initiated oxidation of CH3CHF2 in 700 Torr of air or N2; diluents at 295 +/- 2 K were studied using smog chamber/FTIR techniques. Relative rate methods were used to measure k(Cl + CH3CHF2) = (2.37 +/- 0.31) x 10(-13) and k(OH + CH3CHF2) = (3.08 +/- 0.62) x 10(-14) cm3 molecule(-1) s(-1). Reaction with Cl atoms gives CH3CF2 radicals in a yield of 99.2 +/- 0.1% and CH2CHF2 radicals in a yield of 0.8 +/- 0.1%. Reaction with OH radicals gives CH3CF2 radicals in a yield >75% and CH2CHF2 radicals in a yield 10(10) s(-1)) decomposition to give CH3 radicals and COF2. The remaining approximately 70% become thermalized, CH3CF2O, and undergo decomposition more slowly at a rate of approximately 2 x 10(3) s(-1). At high concentrations (>50 mTorr), NO(x) is an efficient scavenger for CH3CF2O radicals leading to the formation of CH3COF and FNO.
Journal of Physical Chemistry Part A: Molecules, Spectroscopy, Kinetics, Environment and General Theory, 2005, Vol 109, Issue 40, p. 9061-9069