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采用密度泛函理论的B3LYP方法,在6-311+G(d,p)基组水平上研究了C_4H_4S与H_2O_2的微观反应机理,全参数优化了反应势能面上各驻点的几何构型,振动分析和内禀反应坐标(IRC)分析结果证实了中间体和过渡态的真实性,计算所得的键鞍点电荷密度的变化情况也确认了反应过程。结果表明,反应分2步进行,主要经历了O对S的进攻、H转移以及O-O键断裂的历程,决速步骤的活化能为157.3 kJ/mol,能垒高于甲硫醇、甲硫醚和过氧化氢反应的类似步骤。
The B3LYP method of density functional theory was used to study the microscopic reaction mechanism of C_4H_4S and H_2O_2 on the 6-311 + G (d, p) basis set. The geometrical configurations of all stationary sites on the reaction potential surface were optimized by all the parameters. Vibration analysis and intrinsic reaction coordinate (IRC) analysis confirmed the authenticity of the intermediate and transition states, and the calculated charge-saddle point charge density also confirmed the reaction process. The results showed that the reaction proceeded in two steps, mainly undergoing the attack of O on S, H transfer and the cleavage of OO bond. The activation energy of the rate fixing step was 157.3 kJ / mol and the energy barrier was higher than that of methanethiol, A similar procedure for the reaction with hydrogen peroxide.