CH_3SH与OH气相反应机理的理论研究

Theoretical Study on the Reaction Mechanism of CH_3SH with OH under Atmospheric Conditions

采用密度泛函理论,对CH3SH与OH的反应机理进行了量子化学研究。基于B3LYP/6-311++G(d,p)水平,找到了三条可能的反应通道。结果表明:在需要克服能垒的通道中,巯基上氢抽提在动力学和热力学上最有利,活化能为2.7 k J/mol,低于甲基上的氢抽提通道;而对于不需要克服能垒的通道,产物CH3S(OH)H的能量较高,不如前两种通道产物稳定。

A quantum chemical investigation on the reaction mechanism of CH3 SH with OH has been performed using density function theory（ DFT）. Based on B3 LYP /6- 311 ＋ ＋ G（ d,p） calculations,three possible pathways have been found. Comparing to the H- shift of methyl,the results indicated that the H- shift of sulfydryl should be the main pathway with a lower energy barrier of 2. 7 kJ / mol. This pathway was beneficial not only in thermodynamics but also in kinetics. However,the channel involving a barrierless addition gave over to CH3S（ OH） H,which was not so stable owing to the higher energy.