Zhang Yunju, He Bing, Sun Yunxi
College of Chemistry and Chemical Engineering, Key Laboratory of Photoinduced Functional Materials, Mianyang Normal University, Mianyang, 621000, PR China.
College of Chemistry and Life Science, Institute of Functional Molecules, Chengdu Normal University, Chengdu, Sichuan, 611130, PR China.
J Mol Graph Model. 2020 Sep;99:107618. doi: 10.1016/j.jmgm.2020.107618. Epub 2020 Apr 17.
Ab initio BMC-CCSD//B3LYP calculations of the potential energy surfaces (PESs) are associated with the rate constants and branch ratio of products by means of RRKM theories to research the mechanism and product distribution of the CFClCHO with Cl reaction. The singlet and triplet PESs of this reaction have been calculated. Addition/elimination and S2 displacement mechanisms are located on the singlet PES, and S2 displacement and H-abstraction are located on the triplet PES. P1 (CFClCHO + HClO) are expected to the primary products at T ≤ 2400 K, which is by original barrierless Cl addition to the terminal-O atom in CFClCHO and then eliminate HClO molecule, and the branch ratio of products rely on collision energy. The H-abstraction products on the triplet PES are the dominant products at higher temperatures. At 298 and 500 K, the total rate constants are not subject to pressure, conversely, the total rate constants presented typical falloff behavior at 1000 and 3000 K. The atmospheric lifetime of CFClCHO in Cl is around one day. TD-DFT computations imply that IM1 (CFClCHOOCl) and IM2 (CFClCHOClO) will photolyze under the sunlight.
通过RRKM理论，对势能面（PESs）进行从头算BMC-CCSD//B3LYP计算，将其与产物的速率常数和分支比相关联，以研究CFClCHO与Cl反应的机理和产物分布。计算了该反应的单重态和三重态势能面。加成/消除和S2取代机理位于单重态势能面上，S2取代和氢提取位于三重态势能面上。在T≤2400K时，P1（CFClCHO + HClO）预计为主要产物，这是通过Cl最初无势垒地加成到CFClCHO的末端O原子上，然后消除HClO分子得到的，产物的分支比取决于碰撞能量。在较高温度下，三重态势能面上的氢提取产物是主要产物。在298K和500K时，总速率常数不受压力影响，相反，在1000K和3000K时，总速率常数呈现典型的衰减行为。CFClCHO在Cl中的大气寿命约为一天。TD-DFT计算表明，IM1（CFClCHOOCl）和IM2（CFClCHOClO）将在阳光下光解。
