关于CH3CHF2（HFC - 152a）与Cl原子反应的直接从头算动力学研究。

Direct Ab initio dynamics study on the reaction of CH3CHF2 (HFC-152a) with the Cl atom.

作者信息

Sun Hao, He Hongqing, Liu Jingyao, Li Zesheng, Pan Xiumei, Wang Rongshun

机构信息

Institute of Functional Material Chemistry, Faculty of Chemistry, Northeast Normal University, Renmin Street 5268, Changchun, Jilin 130024, P. R. China.

出版信息

Chemphyschem. 2008 Apr 21;9(6):847-53. doi: 10.1002/cphc.200700590.

DOI:10.1002/cphc.200700590

PMID:18357589

Abstract

A direct ab initio dynamics method is used to investigate the hydrogen-abstraction reaction CH(3)CHF(2)+Cl. One transition state is located for alpha-H abstraction, and two are identified for beta-H abstraction. The potential-energy surface (PES) is obtained at the G3(MP2)//MP2/6-311G(d, p) level. Furthermore, the rate constants of the three channels are evaluated by using canonical variational transition-state theory (CVT) with small-curvature tunneling (SCT) contributions over a wide temperature range of 200-2500 K. The dynamic calculations show that the reaction proceeds mainly by alpha-H abstraction over the whole temperature range. The calculated rate constants and branching ratios are both in good agreement with the available experimental values.

摘要

采用直接从头算动力学方法研究氢提取反应CH(3)CHF(2)+Cl。确定了一个用于α-H提取的过渡态，以及两个用于β-H提取的过渡态。在G3(MP2)//MP2/6-311G(d, p)水平上获得了势能面（PES）。此外，通过使用具有小曲率隧穿（SCT）贡献的正则变分过渡态理论（CVT），在200-2500 K的宽温度范围内评估了三个通道的速率常数。动力学计算表明，在整个温度范围内，反应主要通过α-H提取进行。计算得到的速率常数和分支比均与现有的实验值吻合良好。