OBrO+NO反应机理的量子化学研究

Quantum Chemical Investigation on the Reaction Mechanism of OBrO with NO

用密度泛函B3LYP/6-311+G^(##)和高级电子相关偶合簇CCSD(T)/6-311+G^(##)方法研究了 OBrO与NO反应的微观机理。优化得到反应路径上的反应物、过渡态、中间体和产物的几何构型,通过频率振动分析对过渡态和中间体进行了确认。结果表明;该反应是多通道多步骤的放热反应,分别可以在单重态和三重态势能面上进行,OBrO与NO通过加成及加成-消除机理分别形成产物BrONO_2和BrO+NO_2,从能量上看,形成离解产物的通道更容易进行。

The reaction mechanism between OBrO and NO was studied by using the B3LYP/6-311+G* * and the high-level electron-correlation CCSD(T)/6-311+G* * single-point levels. The geometries of reac-tants, transition states, intermediates and products were optimized and verified by frequency analysis. The results show that the reaction is multi-channel and multi-step exothermic. It may proceed on singlet and triplet potential energy surface(PES). OBrO and NO may react via addition or addition-elimination mechanism to form the products BrONO2 and BrO+NO2. In view of energy, the channel of forming the products BrO+NO2 is more favorable.