Knowledge Bank

The interaction between electronic and vibrational motion in linear triatomic molecules in degenerate electronic states, known as the Renner effect, leads to an effective coupling between the angular momentum associated with the bending vibration and that associated with the electronic motions. A consideration of the effects of a small Renner interaction, together with the effects of a small spin-orbit interaction, shows that the rotational energy levels of linear triatomic molecules are not entirely analogous to those of diatomic molecules. Detailed expressions for the form of the rotational energies have been obtained. The general results will be presented.