过渡金属离子Pt+和甲烷气相反应的势能面研究

采用密度泛函理论（DFT）中的B3LYP方法研究了二重态和四重态Pt+与甲烷反应的机理。通过几何构型优化和频率计算，分别获得三个过渡态，并利用内禀反应坐标（IRC）计算进行了验证。在更高的基组水平上计算了单点能，并详细讨论了二重态和四重态的势能面。结果表明在二重态势能面上的反应具有比较低的能垒，是一个放热反应，所以该反应更易于在二重态上进行。氧化加成生成中间体HPt(CH3)+的步骤需要克服一个小小的能垒。

Potential energy surface investigation on the gas phase reaction of transition-metal ion Pt+ with methane

The mechanism of the reaction between Pt+ (doublet and quartet) and CH4 was investigated with B3LYP method in density functional theory (DFT). The transition states were characterized by geometry optimization and frequency computation, confirmed by the intrinsic reaction coordination (IRC) calculation. The single point energies were performed at higher basis set level and compared for the two potential energy surfaces (PES). The PESes (doublet and quartet) were discussed in detail. The results showed that the ground-state doublet state has lower energy barrier and is exoergic. Therefore, the reaction on the doublet PES is favorable. The process of the oxidative addition to form the intermediate HPt(CH3)+ have to overcome a low barrier on the doublet PES.