Reaction of O(3P) with the alkyl iodides: CF3I, CH3I, CH2I2, C2H5I, 1-C3H7I and 2-C3H7I

The kinetics of the reactions between O(3P) and various alkyl iodides (RI) was investigated using the pulsed laser photolysis–resonance fluorescence (PLP–RF) technique at temperatures between 223 and 363 K. The reactions studied were O(3P) + CF3I (1), O(3P) + CH3I (2), O(3P) + CH2I2 (3), O(3P) + C2H5I (4), O(3P) + 1-C3H7I (5), and O(3P) + 2-C3H7I (6). The Arrhenius expressions (units of cm3 molecule−1 s−1) obtained were: k1(223–363 K) = (8.73 ± 1.29) × 10−12exp{−(216 ± 38)/T}, k2(223–363 K) = (9.88 ± 1.67) × 10−12exp{(183 ± 50)/T}, k3 (256–363 K) = (7.36 ± 0.31) × 10−11 cm3 molecule−1 s−1, k4(223–363 K) = (1.58 ± 0.22) × 10−11exp{(239 ± 39)/T} k5(223–363 K) = (1.10 ± 0.17) × 10−11exp{(367 ± 42)/T}, and k6(223–363 K) = (1.84 ± 0.31) × 10−11exp{(296 ± 46)/T}. With the exception of k1 and k3, all the other rate coefficients display a negative temperature dependence, which highlights the importance of association complex formation in reactions of O(3P) + RI.