The Renner effect in a bent triatomic molecule using the adiabatic approach

Abstract

The consequences of the Renner-Teller effect in molecules executing large amplitude bending motion have been treated using an adiabatic approach (Barrow, Dixon and Duxbury [8]) and using a perturbed linear molecule approach (Jungen and Merer [7]). This paper makes detailed numerical comparisons of these two methods in calculations of the vibronic levels of H2S+, NH2 and CO2 +. It is shown that the two methods are completely equivalent. For molecules in which at least one component of a Renner-Split degenerate state is bent the adiabatic approach is computationally considerably the less demanding of the two. However, for linear molecules the Jungen and Merer approach is more rapidly convergent.