铁原子与NO反应的密度泛函理论研究

Density functional theory study of the reaction of iron atom with NO

采用密度泛函理论(DFT)计算研究铁原子与NO反应的相关微观反应机理.全参数优化了四重态和六重态反应势能面上各驻点的几何结构,用频率分析方法和内禀反应坐标(IRC)方法对过渡态进行了验证,得到了该反应的反应势能面曲线,并讨论了势能面的交叉情况.结果表明,该反应为典型的两态反应,反应通道一中出现了一个势能交叉点,反应通道二中出现了两个势能交叉点,反应通道三中出现了三个势能交叉点.势能面上的交叉点能够有效降低反应的活化能,增加反应放热,这在动力学和热力学上都是有利的.

Density functional theory（ DFT） calculations have been carried out to study the micro- mechanism for reaction of iron atom with NO. The geometry optimizations of reactants,transition states,intermediates and products of the reactions of sextet and quartet states were completely optimized,and all the transition states were verified by the vibrational analysis and the intrinsic reaction coordinate calculations. Then the potential energy surface（ PES） were obtained and crossing points were investigated. Results showed that the reaction of iron atom with NO was a typical two- state reaction（ TSR）. One crossing point appeared in the reaction channels 1,Two crossing points appeared in the reaction channels 2,while three crossing points appeared in the reaction channels3 between the quartet and the sextet potential energy surfaces,which would effectively reduce the activation energy and increase the release of reaction heat,play a significant and beneficial role in the kinetic and thermodynamic aspects of this catalytic reaction.