Application of the pade-form hamiltonians for processing of vibration-rotation spectra of diatomic and triatomic molecules

Abstract

The advantages of the use of Pade-type rotational and vibrational-rotational hamiltonians for the process of high resolution molecular spectra are discussed. The brief summary of relevant studies carried out by the authors and a general background are given first. New application to accidental resonances in the water molecule and to diatomics are considered. The relations between Pade-approximants and the molecular potential function are derived on the basis of perturbation theory. Marked improvements in the extrapolation of the HBr rotation-vibration frequencies are achieved from the force field recovered from the precedent fit.