title: Kinetic study of IO radical with RO2 (R = CH(3), C2H5, and CF3) using cavity ring-down spectroscopy.
abstract: The reactions of iodine monoxide radical, IO, with alkyl peroxide radicals, RO(2) (R = CH(3), C(2)H(5), and CF(3)), have been studied using cavity ring-down spectroscopy. The rate constant of the reaction of IO with CH(3)O(2) was determined to be (7.0 +/- 3.0) x 10(-11) cm(3) molecule(-1) s(-1) at 298 K and 100 Torr of N(2) diluent. The quoted uncertainty is two standard deviations. No significant pressure dependence of the rate constant was observed at 30-130 Torr total pressure of N(2) diluent. The temperature dependence of the rate constants was also studied at 213-298 K. The upper limit of the branching ratio of OIO radical formation from IO + CH(3)O(2) was estimated to be <0.1. The reaction rate constants of IO + C(2)H(5)O(2) and IO + CF(3)O(2) were determined to be (14 +/- 6) x 10(-11) and (6.3 +/- 2.7) x 10(-11) cm(3) molecule(-1) s(-1) at 298 K, 100 Torr of N(2) diluent, respectively. The upper limit of the reaction rate constant of IO with CH(3)I was <4 x 10(-14) cm(3) molecule(-1) s(-1).
authors.affiliation: Department of Molecular Engineering, Kyoto University, Kyoto 615-8510, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Enami
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamanaka
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hashimoto
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kawasaki
authors.forename: Yukio
authors.initials: Y
authors.lastname: Nakano
authors.forename: Takashi
authors.initials: T
authors.lastname: Ishiwata