使用密度泛函理论的B3LYP方法、电子偶合相关簇CCSD(T)方法和二次组态相互作用QC ISD(T)方法分别计算了12CH分子的基态(χ2Π)的平衡结构、振动频率、离解能.根据原子分子反应静力学原理,导出了12CH分子基态(χ2Π)的合理离解极限.采用最小二乘法拟合Murrell-Sorbie函数得到了相应的势能函数和与该基态相对应的光谱常数(Be,ωe,αe,和ωeχe),计算结果与实验数据符合得较好.
The equilibrium structure, harmonic frequency and dissociation energy of the ground state of ^12CH are calculated by B3LYP method, CCSD(T) method and QCISD(T) method of density functional theory. Based on the theory of atomic and molecular statics, the reasonable dissociation limit for the ground state (^2Π) of ^12CH is derived. The potential energy curve and relevant spectroscopic constants of this state are obtained by least square fitting to the Murrell-Sorbie function. The calculated results are in good agreement with the experimental data.