New method on constructing analytic potential function of diatomic molecules

A new method on constructing analytical potential energy functions is presented, and then a relatively universal analytical potential energy function for precisely calculating the spectra of diatomic molecules and ions is derived. Furthermore, six kinds of common potential energy curves containing three main potential curves i.e. steady state, metastable state and repulsive state are obtained from this potential energy function. Finally, spectroscopic parameters of thirteen diatomic molecules and ions including BeD-X ² ∑ ⁺, BeT-X ² ∑ ⁺ and Na₂-X ¹ ∑ _g ⁺ etc are calculated by using the potential function, as a consequence, all calculation results are in good agreement with experimental data.