Kinetics of photochlorination of mono- and disubstituted fluoro-, chloro-, and bromomethanes

Environmental effects of large igneous province magmatism: a Siberian perspective

“…The recommended value for E/R is taken from a fit to the data of Orlando and agrees with a fit to the data of Bryukov et al (obtained at room temperature and above) up to 400 K. Above 400K, these latter data increase more rapidly with temperature. The relative rate studies of Goldfinger et al [514], Knox [730], Tschuikow-Roux et al [1323] were performed at temperatures above 298 K and yield significantly higher values for E/R, with the exception of one of the Knox et al determinations (relative to CH 4 ), which gives a value of E/R in good agreement with that recommended. The results of Clyne and Walker [297] are higher than those from any other study and were not used in deriving the recommended parameters.…”

“…The temperature dependence is estimated from a comparison among the Cl and OH reactions with CH 2 F 2 , CH 2 Cl 2 , and CH 2 FCl. The recommended value of E/R (essentially the same as that for the OH + CH 2 FCl reaction) is slightly lower than that determined by Tschuikow-Roux et al [1323], recalculated based on the current recommendation for the rate constant of the reference reaction (Cl + CH 4 ). However, as discussed for other Cl + halomethane reactions, there appears to be a small systematic overestimation in the temperature dependences determined by these authors.…”

“…The temperature dependence is estimated from a comparison with the reactions of Cl with CH 2 Cl 2 and CH 2 Br 2 . The relative rate investigation by Tschuikow-Roux et al [1323] gives a value for k(298 K) only slightly larger than recommended, but a temperature dependence that is significantly stronger and inconsistent with the that recommended for the Cl + CH 2 Cl 2 and Cl + CH 2 Br 2 reactions. (Table: 06-2, Note: 06-2) Back to Table G28.…”

“…Both the room temperature measurements and E/R obtained between 300 K and 400 K by Bryukov et al [190], from a study primarily focused at higher temperatures, are in good agreement with the recommendations. The early relative rate studies by Pritchard et al [1081], Goldfinger et al [514], Knox [729], and Tschuikow-Roux et al [1323], were not used to derive the recommended parameters since they were performed at temperatures above 298 K and, with the exception of Pritchard et al, yield somewhat higher values for E/R. (Table: 06-2, Note: 06-2) Back to Table F87.…”

“…Cl + CH 3 F (HFC-41). The recommended value for k(298 K) is an average of the values from the absolute rate study of Manning and Kurylo [862] and Hitsuda et al [586] and the relative rate studies of Tschuikow-Roux et al [1323], Tuazon et al [1326], and Wallington et al [1398]. The recommended value for E/R is based on the study of [682] and from the relative rate study by Coomber and Whittle [310], which gives a room temperature value a factor of 50 smaller.…”