HO2+HONO及其异构体抽氢反应机理  

Hydrogen Abstraction Reaction Mechanism of HO2 with HONO and Its Isomers

作　　者：王竹青 田汾奕 张勇奇 文明杰 Wang Zhuqing;Tian Fenyi;Zhang Yongqi;Wen Mingjie(Analytical and Testing Center,Sichuan University of Science & Engineering,Zigong 643000;Shaanxi Key Laboratory of Catalysis,School of Chemical & Environment Science,Shaanxi University of Technology,Hanzhong 723000)

机构地区：[1]四川轻化工大学分析测试中心,自贡643000 [2]陕西理工大学化学与环境科学学院陕西省催化基础与应用重点实验室,汉中723000

出　　处：《化学通报》2019年第7期649-654,共6页Chemistry

基　　金：四川省教育厅理科重点项目(17ZA0276);四川理工学院人才引进项目(2016RCL17)资助

摘　　要：本文在CCSD(T)/aug-cc-pVTZ//M06-2X/6-311+G(3d,2p)水平上构建了HO2与HONO及其异构体的反应势能剖面,并对各通道的速率常数进行了计算。结果表明,HONO存在cis-HONO、trans-HONO、HNO2三种不同的异构体,其中HNO2是最稳定的构型。HNO2+HO2反应(R3)能垒比其他两个反应(R1(cisHONO+HO2)和R2(trans-HONO+HO2))的能垒降低了8.2~13.8 kcal·mol^-1。采用传统过渡态理论结合Wigner校正对各反应在240~425 K范围内的速率常数进行了计算。结果表明,反应R3的速率常数比R1和R2的对应值大4~9个数量级,表明HO2+HONO及其异构体的抽氢反应的速率主要取决于HNO2+HO2反应。The mechanism for the reaction of HO2 with HONO and its isomers was investigated at the CCSD(T)/aug-cc-pVTZ//M06-2 X/6-311+G(3 d,2 p)level.The results showed that HONO has three different isomers,labeled as cis-HONO,trans-HONO and HNO2,and HNO2 is the most stable in them.The energy barrier of HO2+HNO2 is lower by 8.2~13.8 kcal·mol^-1 than that of the other two reactions of cis-HONO+HO2 and trans-HONO+HO2.The rate constants of these three reactions were calculated by the traditional transition state theory with Wigner correction in the temperature range of 240~425 K.The calculated results showed that the rate constant of HO2+HNO2 reaction is larger by 4~9 orders of magnitude than those of cis-HONO+HO2 and trans-HONO+HO2,indicating that the total rate constants for the reaction of HO2 with HONO and its isomers mainly lie on the contribution of HO2+HNO2 reaction.

关 键 词：HONO HO2 反应机理 速率常数 

分 类 号：O643.12[理学—物理化学]