【作者】 赵红梅； 刘坤辉； 宋迪； 苏红梅；

【Author】 Hongmei Zhao;Kunhui Liu;Di Song;Hongmei Su;State Key Laboratory of Molecular Reaction Dynamics, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences;

【机构】 中国科学院化学研究所分子反应动力学国家重点实验室,北京分子科学国家实验室；

【摘要】 三重态氧原子和烯烃的反应在深入理解燃烧化学、大气污染以及烃类致癌物的代谢过程中占有重要位置。在实验上提出了反应机理[1]:主要产物为环戊烯氧化物,还可以生成环戊酮,乙烯+丙烯醛,以及环丁基甲醛。在低温凝聚相实验[2]生成乙烯+丙烯醛的反应完全被抑制了。另外对反应产物也存在争议[3]。本文用CCSD(T)//MP2/6-311g**方法研究了反应过程,基于Newton-Lagrange方法找到了T1/S0最低能量交叉点,得到了非绝热反应势能剖面图。由能量最低反应途经线,证明反应产率最高的产物应该为环戊烯氧化物,而不是环戊酮。此外,找到了产生烯醇的路径,是能量允许的反应,预测了烯醇产物的生成。根据计算结果我们提出了新的反应机理(Fig.1),用这个反应机理不但可以合理解释实验现象,而且解决了原反应机理和实验结果相互矛盾的问题。为正确理解基态氧和环戊烯反应提供了理论基础。更多还原

【Abstract】 The reaction mechanism of the ground state oxygen atom O(3P) with cyclopentene is investigated theoretically. The triplet and singlet potential energy surfaces are calculated at the CCSD(T)//MP2/6-311G(d,p) level and the minimum energy crossing points(MECPs) between the two surfaces are located by means of the Newton-Lagrange method, from which the complex nonadiabatic reaction pathways are revealed. Based on the theoretical results, the most probable reaction mechanism of O(3P) with c-C5H8 is described, which agrees with the experimental results nicely, including the condensed phase experiment. At the same time, the newly revealed reaction mechanism clarifies the previous controversial product distribution, and predicts the possible existence of the enol new product, cyclopentenol.更多还原