Reaction Pathway Control via Reactant Vibrational Excitation and Impact on Product Vibrational Distributions: The O + HO2 → OH + O2 Atmospheric Reaction
Reaction Pathway Control via Reactant Vibrational Excitation and Impact on Product Vibrational Distributions: The O + HO2 → OH + O2 Atmospheric Reaction
复制标题
通过反应物振动激发和对产物振动分布的影响来控制反应路径：O HO2 → OH O2 大气反应
DOI：
10.1021/acs.jpclett.2c00053
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发表时间：
2022-02-24
影响因子：
5.7
通讯作者：
Guo, Hua
中科院分区：
文献类型：
--
作者：
Chen, Qixin;Zhang, Shuwen;Guo, Hua
化学反应往往有多个途径，对这些途径的控制具有基础性和实际意义。在这封信中，我们使用最近发展的全维势能面(PES)上的准经典轨迹来研究在大气化学中起重要作用的O+HO2-&Gt；OH+O-2反应的动力学。该反应有两条途径可以得到相同的产物：H提取途径(O-a+HobOc-&Gt；Oah+ObOc)和O()提取途径(O-a+HobOc->；Obh+OaOc)。在热条件下，反应由无障碍的后一通道主导，导致O-2产物的振动激发。然而，我们证明了HO2反应物在其O-H(v(1))振动模式下的激发导致反应路径戏剧性地切换到被激活的H提取通道，从而导致高激发的OH产物振动态分布。讨论了这种动力效应在大气化学中的意义。
Chemical reactions often have multiple pathways, the control of which is of fundamental and practical importance. In this Letter, we examine the dynamics of the O + HO2 -> OH + O-2 reaction, which plays an important role in atmospheric chemistry, using quasi-classical trajectories on a recently developed full-dimensional potential energy surface (PES). This reaction has two pathways leading to the same products: the H abstraction pathway (O-a + HObOc -> OaH + ObOc) and the O( )abstraction pathway (O-a + HObOc -> ObH + OaOc). Under thermal conditions, the reaction is dominated by the latter channel, which is barrierless, leading to vibrational excitation of the O-2 product. However, we demonstrate that excitation of the HO2 reactant in its O-H (v(1)) vibrational mode results in dramatic switching of the reaction pathway to the activated H abstraction channel, which leads to a highly excited OH product vibrational state distribution. The implications of such dynamical effects in the atmospheric chemistry are discussed.