摘要
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。
Density function theory （DFT） B3LYP method was employed to study the reaction mechanism of thiophene arid H2O2 at the level of 6-311＋G（d, p） basis sets. Geometries of the stationary points were completely optimized. The transition states were validated by the vibration analysis and the internal reaction coordinate （IRC） calculations. The results indicated that the title reaction may involve two steps, which might include the attack of O to S, O---O bond cleavage and hydrogen transfer. The first step of the title reaction constitutes the rate-determining step, the corresponding activation energy is 157.3 kJ/mol. And thiophen has a higher energy barrier than dimethyl sulfide or thiol in the oxidation reaction by H2O2.
出处
《计算机与应用化学》
CAS
CSCD
北大核心
2013年第12期1503-1507,共5页
Computers and Applied Chemistry
基金
国家级大学生创新训练计划项目(201210449107)
山东省自然科学基金项目(ZR2010BL016)
滨州学院青年人才创新工程项目(BZXYQNLG201202)
滨州学院科研基金项目(BZXYG1305)
关键词
噻吩
过氧化氢
反应机理
电子密度拓扑分析
thiophene
hydrogen peroxide
reaction mechanism
topological analysis of electronic density
