Fe_2和NO反应的密度泛函理论研究

采用密度泛函理论(DFT)中的B3LYP方法在6-311+G(d,p)的计算水平上研究了Fe_2铁簇与NO反应的相关微观机理.全参数优化了八重态以及十重态反应势能面上各驻点的几何结构,并用频率分析法以及内禀反应坐标(IRC)方法对过渡态进行了验证,得到了该反应的微观反应路径和反应势能面(PESs).用"两态反应"分析反应机理,势能面上的两个交叉点能有效地降低反应的活化能,这在动力学上和热力学上都是有利的.N原子脱离化合物为整个反应的速控步骤.

Density Functional Theory Study of Two State Reactivity of NO Activation on Iron Dimer

The mechanism of Fe2+NO (octet and dectet) was calculated by the Density Functional Theory (DFT) with the B3LYP methods combined with the 6-311+G (d, p) basis set. The geometry optimizations of reactants, transition states, intermediates and products of the reactions of triplet and quartet states were completely optimized, and all the transition states were verified by the vibration analysis and the intrinsic reaction coordinate calculations. The "Two State Reactivity (TSR)" was used to analyze the reaction mechanism; result showed that the two crossing points can lower the activation energy of reaction effectively, which play a beneficial role in the kinetic and thermodynamic aspects of this reaction. And the breaking of Fe-N bond is the rate-determining step.