Analytical potentials for triatomic molecules from spectroscopic data

A general procedure has been developed for constructing analytical potential functions for triatomic molecules which have more than one minimum, these minima not necessarily being related by symmetry. Explicit potentials have been derived for the ground states of HO₂, SO₂ and ClO₂. For HO₂ a linear hydrogen bonded structure O-H----O is predicted as a metastable species. In the case of SO₂ a second minimum corresponding to the species SOO is predicted and ab initio calculations at the SCF MO double-zeta level have been made to establish the geometry and energy of this. For ClO₂ it has been assumed that the spectroscopically observed states of OClO and ClOO are separate minima on the same surface.