Zhang Yunju, He Bing, Sun Yuxi
Key Laboratory of Photoinduced Functional Materials, Mianyang Normal University, Mianyang, 621000, People's Republic of China.
College of Chemistry and Life Science, Institute of Functional Molecules, Chengdu Normal University, Chengdu, 611130, Sichuan, People's Republic of China.
Sci Rep. 2020 Jul 6;10(1):11078. doi: 10.1038/s41598-020-68049-4.
The singlet and triplet potential energy surfaces of the ClO• radical reaction with the CHCFClO• radical have been investigated at the CCSD(T)/cc-pVTZ level based on the optimized geometries at the B3LYP/6-311++G(d,p) level. On the singlet potential energy surfaces (PES), the possible reaction involves association-dissociation, direct H-abstraction and Nucleophilic Substitution 2 (S2) mechanisms. On the triplet PES, S2 displacement and direct H-abstraction reaction pathways have been investigated, which are less competitive compared with the reaction pathways on the singlet PES. The rate constants have been calculated at 10 to 10 atm and 200-3,000 K by Rice-Ramsperger-Kassel-Marcus (RRKM) theory for the important product pathways. At 200-800 K, IM1 produced (CHCFClOOOCl) by collisonal deactivation is dominant; at high temperatures, the production P1 (CHCFO + ClOOCl) becomes dominate. The calculated rate constants for CHCFClO• + ClO• are good agreement with the available experimental value. The atmospheric lifetime of CHCFClO• in ClO• is around 3.27 h. TD-DFT computations imply that IM1 (CHCFClOOOCl), IM2 (CHCFClOOClO) and IM3 (CHCFClOClO) will photolyze under the sunlight.
基于在B3LYP/6-311++G(d,p)水平上优化的几何结构，在CCSD(T)/cc-pVTZ水平上研究了ClO•自由基与CHCFClO•自由基反应的单重态和三重态势能面。在单重态势能面上，可能的反应涉及缔合-解离、直接氢提取和亲核取代2（S2）机制。在三重态势能面上，研究了S2取代和直接氢提取反应途径，与单重态势能面上的反应途径相比，它们的竞争力较小。通过Rice-Ramsperger-Kassel-Marcus（RRKM）理论计算了重要产物途径在10至10 atm和200-3000 K下的速率常数。在200-800 K时，通过碰撞失活产生的IM1（CHCFClOOOCl）占主导；在高温下，产物P1（CHCFO + ClOOCl）的生成占主导。计算得到的CHCFClO• + ClO•的速率常数与现有的实验值吻合良好。CHCFClO•在ClO•中的大气寿命约为3.27小时。TD-DFT计算表明，IM1（CHCFClOOOCl）、IM2（CHCFClOOClO）和IM3（CHCFClOClO）将在阳光下发生光解。
