The vibrational Stark effect

Abstract

Expressions for the frequency and intensity of the fundamental‐vibrational transitions of a polyatomic molecule in the presence of a uniform or nonuniform electric field are reported. They have been developed on the basis of perturbation theory and take into account, individually, first‐order electrical and mechanical anharmonicity. They are more general than previously‐used expressions, since terms which are quadratic in the field strength are included. As an example of their use and of their interpretative capability, they are applied to CO.