Song Hongwei, Xie Weiyu, Zhang Chaoyang, Yang Minghui
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China.
Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang 621900, China.
J Phys Chem A. 2022 Feb 10;126(5):663-669. doi: 10.1021/acs.jpca.1c08399. Epub 2022 Jan 26.
Mode specificity not only sheds light on reaction dynamics but also opens the door for chemical reaction control. This work reports a state-of-the-art full-dimensional quantum dynamics study on the prototypical hydrogen abstraction reaction of hydrogen with ammonia, which serves as a benchmark for advancing our fundamental understanding of polyatomic reaction dynamics. By taking advantage of the (3 + 1) Radau-Jacobi coordinates, the bond-specific probabilities are resolved with the reactant NH initiated from either a non-degenerate or degenerate stretching vibrational state. The observed different atom-specific abstraction probabilities from individual states of the degenerate pair are rationalized in the local mode representation according to the different vibrational energy deposited in each N-H bond. It is verified that the three H atoms in NH have the same abstraction probability as that from the degenerate pair and the linear combination of the degenerate pair gives the same reaction probability. In addition, the symmetric and asymmetric stretching modes of the reactant NH have comparable efficacies on driving the reaction.
模式特异性不仅有助于揭示反应动力学，还为化学反应控制打开了大门。这项工作报道了一项关于氢与氨的典型氢提取反应的前沿全维量子动力学研究，该反应是推进我们对多原子反应动力学基本理解的一个基准。通过利用(3 + 1)拉道 - 雅可比坐标，从非简并或简并拉伸振动态起始的反应物NH的键特异性概率得以解析。根据简并对中各个状态在每个N - H键中沉积的不同振动能量，在局域模式表示中对从简并对的各个状态观察到的不同原子特异性提取概率进行了合理化解释。已证实NH中的三个H原子具有与简并对相同的提取概率，并且简并对的线性组合给出相同的反应概率。此外，反应物NH的对称和不对称拉伸模式在驱动反应方面具有相当的效率。
