论文部分内容阅读
应用QCISD(T)//B3LYP/6-311+G(3df,2p)方法研究了HSO和HOO的反应机理,构建了反应的单、三重态势能剖面。研究发现,HSO和HOO反应在单、三重态势能面上包含2种机理,一种是抽氢机理:HSO中氧原子抽取HOO中氢原子或HOO的端基氧原子抽取HSO的氢原子。另一种是耦合脱水机理:HOO的OH基团与HSO的氢原子结合生成产物H2O和SOO。结果表明,抽氢机理有利于发生且HOO中端基氧原子夺取HSO的氢原子为抽氢主通道。此外发现抽氢反应容易发生在三重态势能面上,对应过渡态3TS1的活化能为6.73(k J·mol-1)。基于统计热力学原理预测了标题反应中所有稳定物种的生成焓(Δf H?298/Κ),熵(S?298/Κ)和热容(Cp,200～1000)Κ。理论结果与实验数据较为接近。
The reaction mechanism of HSO and HOO was studied by QCISD (T) // B3LYP / 6-311 + G (3df, 2p) method, and the single and triplet potential energy profiles of the reaction were constructed. It is found that there are two mechanisms for the reaction between HSO and HOO on the single and triplet potential energy surfaces. One is the hydrogen abstraction mechanism. The hydrogen atoms of HO or HOO are extracted by oxygen atoms in HSO. The other is coupled dehydration mechanism: HOO OH group and HSO hydrogen atoms combine to produce the product H2O and SOO. The results show that the hydrogen abstraction mechanism is favorable for hydrogen atoms to take place and HCO end-terminal oxygen atoms take HSO as the main channel of hydrogen abstraction. In addition, it was found that the hydrogen abstraction reaction easily occurred on the triplet potential energy surface, and the activation energy of 3TS1 corresponding to the transition state was 6.73 (kJ · mol-1). Based on the statistical thermodynamic principle, the enthalpies of formation (Δf H? 298 / K), entropy (S? 298 / K) and heat capacity (Cp, 200-1000) K of all the stable species in the title reaction were predicted. The theoretical result is close to the experimental data.