Kinetics and mechanism of the reaction of CH3 and CH3O with ClO and OClO at 298 K
Abstract
A discharge-flow system equipped with a laser-induced fluorescence cell to detect the methoxyl radical and a quadrupole mass spectrometer to detect both the chlorine monoxide and chlorine dioxide radicals has been used to measure the rate constants for the reactions CH3+ ClO → products (1), CH3O + ClO → products (2), CH3+ OClO → products (3), CH3+ OClO → products (4), at T= 298 K and P= 1–3 Torr. The observed products of these reactions are CH3O for reaction (1), HOCl for reaction (2), and CH3O and ClO for reaction (3). For reaction (4), CH3OCl is a possible product. The rate constants derived for reactions (1)–(4) are: k1=(1.3 ± 0.4)× 10–10 cm3 molecule–1 s–1; k2=(1.3 ± 0.3)× 10–11 cm3 molecule–1 s–1; k3=(1.6 ± 0.3)× 10–11 cm3 molecule–1 s–1; k4=(1.5 ± 0.5)× 10–12 cm3 molecule–1 s–1. The likely mechanisms for reactions (1)–(4) are briefly discussed.