Electric Dipole and Electronic Transition Moment Functions in Molecular Spectroscopy

Abstract

The knowledge of the electric dipole moment functions (EDMF’s) and the electronic transition moment functions (ETMF’s) allows the evaluation of the radiative transition probabilities for arbitrary transitions between the rotational — vibrational levels of one or two electronic states, provided the potential energy functions are known. Moreover, since dipole moments directly reflect the charge distribution in the molecule, the EDMF’s provide information about the character of the electronic wavefunctions and their change with the molecular geometry coordinates. Maxima or minima in the dipole moment or transition moment functions are often related to avoided crossings of electronic states with different polarities.