Effective potential energy curves of the ground electronic states of isotopomers of the methylidyne radical CH are constructed by morphing accurate ab initio potential energy curves within the framework of Jenč’s reduced potential energy curve (RPC) approach. The morphing is performed by fitting the RPC parameters to available experimental ro-vibrational data. In turn, the resulting potential energy curves are used to determine the radial property functions describing the spin-orbit and fine and hyperfine energy patterns of the spin-ro-vibrational energy levels by morphing their ab initio approximants or by a direct fitting to experiment. The resulting functions enable reliable predicting outside prospected energy regions, and a quantitative probing of the impacts of external perturbations on the observed spectra.

通过在 Jenč 的还原势能曲线 (RPC) 方法的框架内对准确的从头算势能曲线进行变形，构建了亚甲基自由基 CH 的同位素基体电子态的有效势能曲线。变形是通过将 RPC 参数拟合到可用的实验旋转振动数据来执行的。反过来，由此产生的势能曲线用于确定描述自旋轨道以及自旋振动能级的精细和超精细能量模式的径向特性函数，方法是通过从头开始变形近似值或直接拟合实验。由此产生的函数能够可靠地预测外部预期能量区域，并定量探测外部扰动对观察到的光谱的影响。