Investigating Tunneling-Controlled Chemical Reactions through Ab Initio Ring Polymer Molecular Dynamics
Investigating Tunneling-Controlled Chemical Reactions through Ab Initio Ring Polymer Molecular Dynamics
复制标题
通过从头算环聚合物分子动力学研究隧道控制的化学反应
DOI：
10.1021/acs.jpclett.1c01630
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Huo, Pengfei
中科院分区：
文献类型：
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作者：
Li, Xinyang;Huo, Pengfei
我们使用从头算环聚合物分子动力学（RPMD）的方法来研究隧道控制的甲基羟基卡宾反应。核隧穿效应使分子能够克服经典方法无法克服的势垒。在低温条件下，内在量子隧穿效应可以促进化学反应的途径，这是有利于既不是化学也不是动力学。这种行为被称为隧道控制的化学反应，被认为是化学反应控制的第三个范例。在这项工作中，我们使用从头计算RPMD方法，将隧道效应在我们的量子动力学模拟和研究在不同温度下的两个竞争反应途径的反应动力学。这里得到的反应速率常数与实验测得的速率非常吻合。我们证明了在一个现实的分子系统中使用从头计算RPMD速率计算的可行性，并提供了一个有趣的和重要的例子，为未来的调查占主导地位的量子隧穿效应的反应机制。
We use the ab initio ring polymer molecular dynamics (RPMD) approach to investigate tunneling-controlled reactions in methylhydroxycarbene. Nuclear tunneling effects enable molecules to overcome the barriers which cannot be overcome classically. Under low-temperature conditions, intrinsic quantum tunneling effects can facilitate the chemical reaction in a pathway that is favored neither thermodynamically nor kinetically. This behavior is referred to as the tunneling-controlled chemical reaction and is regarded as the third paradigm of chemical reaction controls. In this work, we use the ab initio RPMD approach to incorporate the tunneling effects in our quantum dynamics simulations and investigate the reaction kinetics of two competitive reaction pathways at various temperatures. The reaction rate constants obtained here agree extremely well with the experimentally measured rates. We demonstrate the feasibility of using ab initio RPMD rate calculations in a realistic molecular system and provide an interesting and important example for future investigations of reaction mechanisms dominated by quantum tunneling effects.