Liu Jinfeng, Liu Yanqing, Yang Jinrong, Zeng Xiao Cheng, He Xiao
Department of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, China.
J Phys Chem Lett. 2021 Apr 8;12(13):3379-3386. doi: 10.1021/acs.jpclett.1c00448. Epub 2021 Mar 30.
The reaction of Criegee intermediates with water vapor has been widely known as a key Criegee reaction in the troposphere. Herein, we investigated the reaction of the smallest Criegee intermediate, CHOO, with a water cluster through fragment-based molecular dynamics simulations at the MP2/aug-cc-pVDZ level. Our results show that the CHOO-water reaction could occur not only at the air/water interface but also inside the water cluster. Moreover, more than one reactive water molecules are required for the CHOO-water reaction, which is always initiated from the Criegee carbon atom and ends at the terminal Criegee oxygen atom via a directional proton transfer process. The observed reaction pathways include the loop-structure-mediated and stepwise mechanisms, and the latter involves the formation of transient HO. The lifetime of transient HO is on the order of a few picoseconds, which may impact the atmospheric budget of the other trace gases in the actual atmosphere.
在对流层中，克里奇中间体与水蒸气的反应是广为人知的关键克里奇反应。在此，我们通过基于片段的分子动力学模拟，在MP2/aug-cc-pVDZ水平上研究了最小的克里奇中间体CHOO与水团簇的反应。我们的结果表明，CHOO与水的反应不仅可以发生在空气/水界面，也可以发生在水团簇内部。此外，CHOO与水的反应需要不止一个反应性水分子，该反应总是从克里奇碳原子开始，通过定向质子转移过程在末端克里奇氧原子处结束。观察到的反应途径包括环结构介导机制和逐步机制，后者涉及瞬态HO的形成。瞬态HO的寿命约为几皮秒，这可能会影响实际大气中其他痕量气体的大气收支。
