CO和OH自由基反应机理的量子化学研究

用密度泛函理论(DFT)的B3LYP方法,在6-311 G(d,p)基组水平下研究了CO与OH自由基反应的微观机理.全参数优化了反应过程中各反应物、中间体、过渡态和产物的几何构型,振动分析结果证实了中间体和过渡态的真实性,IRC计算结果进一步证实了过渡态的真实性.在G3水平上计算了它们的能量,OH自由基与CO反应机理的研究结果显示:OH自由基与CO反应为双通道反应过程,分别为(1)CO OH→IM1→TS1→CO2 H;(2)CO OH→IM1→TS2→IM2→TS3→CO2 H.其中通道(2)的活化能较低,为主要反应通道.

Quantum Chemistry Study on the Reaction Mechanism of CO with OH

In this paper, B3LYP method was performed to study the reaction mechanism of CO with OH radical. The geometries of reactants, intermediates, transition states and products were optimized by B3LYP method at the 6-311 G(d,p) level. Intermediates and transition states were confirmed by the results of vibration analyses. Transition states were further confirmed by the IRC calculation results. G3 method was performed to compute the energies. From the results, one can see that the CO OH reaction has two pathways, which are (1)CO OHIM1TS1CO2 H;(2)CO OHIM1TS2IM2TS3CO2 H. Comparing the two pathways' activation energies, one can also find that the main reaction pathway is CO OH IM1TS2IM2TS3CO2 H.