FTIR PRODUCT STUDY OF THE REACTION OF CH3OCH2O2+HO2

Fourier transform infrared spectroscopy was used to identify CH3OCHO and CH3OCH2OOH as products of the gas-phase reaction of CH3OCH2O2 radicals with HO2 radicals. At 700 Torr and 295 +/- 2 K, branching ratios of k1a/k1 = 0.53 +/- 0.08 and k1b/k1 = 0.40 +/- 0.04 were established. Quoted errors are 2 standard deviations together with our estimate of systematic uncertainties. (CH3OCH2O2+HO2-->CH3OCH2OOH+O2 (1a), CH3OCH2O2+HO2-->CH3OCHO+O2+ H2O (1b).) This result is discussed with respect to previous literature data and to computer models of atmospheric chemistry. As part of this work, the rate constants for the reaction of Cl atoms with CH3OCH2OOH and CH3OCHO were determined to be (6.1 +/- 0.3) x 10(-11) and (1.4 +/- 0.1) x 10(-12) cm3 molecule-1 s-1, respectively.