A Kinetic Study of the Reaction between Ethylperoxy Radicals and HO2

Article abstract of DOI:10.1021/j100059a016

Flash photolysis-time-resolved UV spectroscopy is used to measure the rate constant for the C2H5O2 + HO2 reaction over the temperature range of 210-363 K.The radicals are generated by photolysis of F2 in the presence of H2 and ethane.The rate constant for the F + C2H6 reaction is measured relative to the F + H2 reaction to be k₁ = (7.1^+2.1_-1.6)*10^-10e^{(-347+/-69)/T} cm³ s^-1.In order to ascertain time-resolved concentrations, the HO2 UV absorption cross section and its self-reaction rate constant have been remeasured.The UV cross section is in good agreement with previous reports, with ?_max = 0.041 Angstroem² at 203 nm.The self-reaction rate constant of k₅ = (2.8+/-0.5)*10^-13e^(594+/-55)/T cm³ s^-1 is in excellent agreement with the currenty recommended value.The rate constant for the C2H5O2 + HO2 reaction is k₇ = (6.9^+2.1_-1.6)*10^-13e^(702+/-69)/T cm³ s^-1.This result is discussed with regard to the discrepancy which exists between the two previous measurements of this rate constant.