物理化学学报 >> 2016, Vol. 32 >> Issue (3): 701-710.doi: 10.3866/PKU.WHXB201512303

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HS+HO2气相反应机理及主通道速率常数的理论研究

张田雷1,*(),杨晨1,凤旭凯1,王竹青2,王睿1,刘秋丽1,张鹏1,王文亮3,*()   

  1. 1 陕西理工学院化学与环境科学学院, 陕西省催化基础与应用重点实验室, 陕西汉中 723001
    2 山东省科学院海洋仪器仪表研究所, 山东省海洋环境监测技术重点实验室, 山东青岛 266001
    3 陕西师范大学化学化工学院, 陕西省大分子科学重点实验室, 西安 710062
  • 收稿日期:2015-11-20 发布日期:2016-03-04
  • 通讯作者: 张田雷,王文亮 E-mail:ztianlei88@163.com;wlwang@snnu.edu.cn
  • 基金资助:
    国家自然科学基金(21473108, 21207081);陕西理工学院科研计划项目(SLGQD13(2)-3, SLGQD13(2)-4)

Theoretical Study on the Atmospheric Reaction of HS with HO2: Mechanism and Rate Constants of the Major Channel

Tian-Lei ZHANG1,*(),Chen YANG1,Xu-Kai FENG1,Zhu-Qing WANG2,Rui WANG1,Qiu-Li LIU1,Peng ZHANG1,Wen-Liang WANG3,*()   

  1. 1 Shaanxi Province Key Laboratory of Catalytic Fundamental & Application, School of Chemical & Environment Science, Shaanxi University of Technology, Hanzhong 723001, Shaanxi Province, P.R.China
    2 Shandong Provincial Key Laboratory of Ocean Environment Monitoring Technology, Shandong Academy of Sciences Institute of Oceanographic Instrumentation, Qingdao 266001, Shandong Province, P.R.China
    3 Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, P.R.China
  • Received:2015-11-20 Published:2016-03-04
  • Contact: Tian-Lei ZHANG,Wen-Liang WANG E-mail:ztianlei88@163.com;wlwang@snnu.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(21473108, 21207081);Funds of Research Programs of ShaanxiUniversity of Technology, China(SLGQD13(2)-3, SLGQD13(2)-4)

摘要:

采用CCSD(T)/6-311++G(3df, 2pd)//B3LYP/6-311+G(2df, 2p)双水平计算方法构建了HO2+HS反应体系的单、三重态反应势能面,并对该反应主通道的速率常数进行了研究。研究结果表明,标题反应经历了八条反应通道,其中三重态反应通道R1是标题反应主通道。此通道包含路径Path 1 (R → 3IM1 → 3TS1 → P1(3O2+H2S))和Path 1a (R → 3IM1a → 3TS1a → P1(3O2+H2S))两条路径。利用经典过渡态理论(TST)与变分过渡态理论(CVT)并结合小曲率隧道效应模型(SCT),分别计算了主路径Path 1和Path 1a在200-800 K温度范围内的速率常数kTSTkCVTkCVT/SCT,在此温度区间内路径Path 1和Path 1a具有负温度系数效应。速率常数计算结果显示,对主路径Path 1和Path 1a而言,变分效应在计算温度段内有一定影响,与此同时量子力学隧道效应在低温段有显著影响。路径Path 1和Path 1a的CVT/SCT速率常数的三参数表达式分别为k1CVT/SCT(200-800 K) = 1.54×10-5T-2.70exp(1154/T) cm3 ·molecule-1·s-1k1aCVT/SCT(200-800 K) = 5.82×10-8T-1.84exp(1388/T) cm3·molecule-1·s-1

关键词: HS, HO2, 势能面, 反应机理, 速率常数

Abstract:

The mechanism for the biradical reaction of HS with HO2 is investigated at the CCSD(T)/6-311++ G(3df, 2pd)//B3LYP/6-311+G(2df, 2p) level on both the singlet and triplet potential energy surfaces, along with rate constant calculations of the major channel.The results show that there are eight reaction channels involved in the HS+HO2 reaction system.The major channel R1 of the title reaction occurs on the triplet potential energy surfaces, and includes two pathways: Path 1 (R → 3IM1 → 3TS1 → P1(3O2+H2S)) and Path 1a (R → 3IM1a → 3TS1a → P1(3O2+H2S)).The rate constants kTST, kCVT, and kCVT/SCT of Paths 1 and 1a for Channel R1 were evaluated using classical transition state theory (TST) and the canonical variational transition state theory (CVT), in which the small-curvature tunneling correction was included.The calculated results show that kTST, kCVT, and kCVT/SCT of these two pathways decrease with rising temperature within the temperature range of 200-800 K.The variational effect was not negligible in the entire process of Path 1 and Path 1a, at the same time, the tunneling effect was considerable at lower temperature.The fitted three-parameter expressions of kCVT/SCT for Paths 1 and 1a are k1CVT/SCT(200-800 K) = 1.54×10-5T-2.70exp(1154/T) cm3·molecule-1·s-1 and k1aCVT/SCT (200-800 K) = 5.82×10-8T-1.84exp(1388/T) cm3·molecule-1·s-1, respectively.

Key words: HS, HO2, Potential energy surface, Reaction mechanism, Rate constant

MSC2000: 

  • O643.1