Liu Lijie, Fu Yanlin, Wu Hao, Lu Xiaoxiao, Dong Wenrui, Wang Xingan, Zhang Dong H, Fu Bina
Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China.
State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
J Phys Chem Lett. 2025 Jan 16;16(2):460-467. doi: 10.1021/acs.jpclett.4c03327. Epub 2025 Jan 1.
Criegee intermediates (CIs) are potentially significant oxidants and a major source of OH radicals in the troposphere. The -CHCHOO intermediate has been confirmed as a crucial component of CIs in the atmospheric environment. Although previous studies have provided some experimental and theoretical rate constants, inconsistencies among these data remain, and the experimental data do not cover the full range of temperatures present in the troposphere. Here, we developed an accurate full-dimensional (27-dimensional) potential energy surface (PES) for the -CHCHOO + HO reaction using the fundamental invariant-neural network approach and performed the ring polymer molecular dynamics (RPMD) calculations on the basis of this PES for this complex multichannel reaction involving 11 atoms, posing a significant challenge due to current computational limits. The RPMD rate coefficients between 250 and 350 K are ∼1 order of magnitude larger than the results based on variational transition-state theory. This discrepancy highlights pronounced dynamical effects and moderate quantum effects across the two hydrogen-transfer channels. This work provides reliable rate coefficients for the title reaction, which are vital for evaluating the atmospheric fate of -CHCHOO and for developing reliable atmospheric models.
克里吉中间体（CIs）是对流层中潜在的重要氧化剂和羟基自由基的主要来源。-CHCHOO中间体已被确认为大气环境中CIs的关键成分。尽管先前的研究提供了一些实验和理论速率常数，但这些数据之间仍存在不一致性，并且实验数据并未涵盖对流层中存在的所有温度范围。在此，我们使用基本不变神经网络方法为-CHCHOO + HO反应开发了一个精确的全维（27维）势能面（PES），并基于此PES对这个涉及11个原子的复杂多通道反应进行了环聚合物分子动力学（RPMD）计算，由于当前的计算限制，这构成了重大挑战。250至350 K之间的RPMD速率系数比基于变分过渡态理论的结果大约1个数量级。这种差异突出了两个氢转移通道中明显的动力学效应和适度的量子效应。这项工作为标题反应提供了可靠的速率系数，这对于评估-CHCHOO的大气归宿以及开发可靠的大气模型至关重要。
