Temperature Dependence of the Rate Constants and Branching Ratios for the Reactions of Cl<sup>-</sup>(D<sub>2</sub>O)<sub>1</sub><sub>-</sub><sub>3</sub> with CH<sub>3</sub>Br and Thermal Dissociation Rates for Cl<sup>-</sup>(CH<sub>3</sub>Br)
作者:John V. Seeley、Robert A. Morris、A. A. Viggiano、Haobin Wang、William L. Hase
DOI:10.1021/ja960872u
日期:1997.1.1
The rateconstants and products for the reactions of Cl-(D2O)n + CH3Br (n = 1−3) have been measured. The n = 1 reaction was studied from 238 to 478 K. The rateconstant is well described by k = (6.0 × 10-10) exp(−1270/T) cm3 s-1. We determined the reaction mechanism to be ligand switching to produce Cl-(CH3Br) followed by thermal decomposition of the complex. Cl-(CH3Br) decomposition produces greater
已经测量了 Cl-(D2O)n + CH3Br (n = 1−3) 反应的速率常数和产物。在 238 到 478 K 范围内研究了 n = 1 反应。速率常数由 k = (6.0 × 10-10) exp(-1270/T) cm3 s-1 很好地描述。我们确定反应机制是配体转换以产生 Cl-(CH3Br),然后复合物的热分解。Cl-(CH3Br) 分解产生大于 90% 的 Br- + CH3Cl,其余为 Cl- + CH3Br。Cl-(CH3Br) + He 速率常数由 k = (4.5 × 10-10) exp(-2260/T) cm3 s-1 很好地描述。RRKM 理论用于模拟 Cl-(CH3Br) 的分解。如果使用 22.5 kJ mol-1 的中心势垒高度,结果与我们的实验结果一致。n = 2 和 3 反应也通过配体转换和热分解进行。从 203 到 298 K 研究了 n = 2 反应。速率常数由