OH^-与CH_2ClF反应的阴离子产物通道(英文)

Anionic Production Pathways Involved in the Reaction between OH^- and CH_2ClF

理论研究了羟基负离子(OH-)与氟氯代甲烷(CH2ClF)反应的阴离子产物通道.分别在B3LYP/6-31+G(d,p)和B3LYP/6-311++G(2d,p)水平上得到反应势能面上各关键物种的优化构型,进而计算得到谐振频率和零点能.基于CCSD(T)/6-311+G(3df,3dp)水平的相对能量,描述了由质子转移和双分子亲核取代(SN2)过程生成各阴离子产物的途径.各阴离子产物途径势垒的计算结果表明质子转移过程是实验中的主要产物通道,与以往实验测量的结论相符.此外,计算还显示双分子亲核取代过程得到了非典型的阴离子产物,其中动力学效应可能会导致F-的生成.

The anionic production pathways involved in the reaction between hydroxide anion （OH-） and chlorofluoromethane （CH2ClF） were theoretically investigated. The optimized geometries of all the important species on the reaction potential energy surface were obtained at the B3LYP/6-31＋G（d,p） and B3LYP/6-311＋＋G（2d,p） levels. Consequently, harmonic vibrational frequencies and zero point energies （ZPEs） were calculated. Based on the relative energies of all the species that were calculated at the CCSD（T）/6-311＋G（3df,3dp） level, the anionic production channels for the H＋-abstraction and the bimolecular nucleophilic substitution （SN2） reaction processes are elaborated upon. According to the calculated barrier heights for the production pathways, the H＋-abstraction channel is dominant, which agrees very well with previous experimental conclusions. In addition, non-typical anionic products are suggested to form during the SN2 reaction processes where the serious dynamic effect probably causes the SN2 reaction process to produce F-.