Expansion of the Rotational Energy of Diatomic Molecules into a Continued Fraction

A new expansion of the rotational energy of diatomic molecules, in the form of a continued fraction has been investigated. The considered formula is applied in calculation of molecular constants and reproduction of rotational spectra of rigid-, semirigid- and van der Waals-type molecules. A physical interpretation of semiempirical expansion parameters is proposed and a connection between the method considered and the Dunham approach is also discussed.