摘要
在B3LYP/CBSB7水平上优化了CH2(β)CH2(α)OH+HO_2反应各驻点物种的几何构型,并在相同水平上通过频率计算和内禀反应坐标(IRC)对过渡态结构进行了分析,并对其连接性进行了验证.采用CBS-QB3方法对B3LYP/CBSB7水平上优化后各驻点物种做了单点能校正,分别构建了CH2(β)CH2(α)OH+HO_2反应体系在单、三重态的势能剖面.研究结果表明,在单、三重态势能剖面上,反应分别经历了:(a)HO_2中的端基(非端基)O抽取CH_2CH_2OH羟基中的H;(b)HO_2中的端基(非端基)O抽取CH_2CH_2OH中C(α)上的H原子;(c)CH_2CH_2OH中C(β)抽取HO_2中的H.从势能面看,三重态反应通道R9为优势通道.此外,通过200~1 000K内各通道的速率常数以及分支比,证实了生成产物CH3CH2OH+3 O_2的通道R9为反应主通道.
The geometrical structures of the reactants,intermediates,transition states and products for CH 2CH 2OH+HO 2 reaction are optimized at the B3LYP/CBSB7 level of theory.At the same level,the frequency calculation,the analysis of intrinsic reaction coordinates(IRC)transition state structure and connectivity are verified.The single-point energy correction for each stationary species at B3LYP/CBSB7 level is performed by using CBS-QB3 method.Then,the potential energy profiles of CH 2(β)CH 2(α)OH+HO 2 reaction system in the singlet and the triplet states are constructed.The calculated results show that the reaction primarily undergoes through three kinds of hydrogen abstractions:(a)the terminal and non-terminal O atom in HO 2 extracts H atom of hydroxyl in CH 2CH 2OH;(b)the terminal and non-terminal O atom in HO 2 extracts H atom of C(α)in CH 2CH 2OH;(c)C(β)of CH 2CH 2OH abstracts H atom in HO 2.The favorable channel is the channel R9.Besides these,in the temperature range of 200~1 000 K,the main rate constant and branching ratios are calculated,which further indicates that the channel R9 is the main channel of reaction.
作者
许琼
文明杰
姚秋月
李娜
王睿
XU Qiong;WEN Ming-jie;YAO Qiu-yue;LI Na;WANG Rui(Shaanxi Key Laboratory of Catalysis,College of Chemical&Environment Science,Shaanxi University of Technology, Hanzhong 723000,Shaanxi,China)
出处
《西北师范大学学报(自然科学版)》
CAS
北大核心
2018年第6期68-74,81,共8页
Journal of Northwest Normal University(Natural Science)
基金
陕西理工大学大学生创新创业训练计划项目(2017112).