Long-range ab initio potential energy surface for the ground electronic state of the ozone molecule with the accurate dissociation asymptote

Abstract

In this work an excellent agreement was achieved between the empirical (9230.08 ± 4.85 cm−1) and theoretical (9230.70 cm−1) values of the first dissociation limit (De) of O3. Ab initio multireference calculations were performed for the first time using the extended complete active space [CAS(24,15)] reference in the icMRCI(Q) method combined with the extrapolation to the complete basis set limit [CBS(56Z)] and with the inclusion of the spin–orbit coupling between 9 multiplet electronic states approaching De. Finally, the full-dimensional potential energy surface was developed in the scattering coordinates for the long-range region toward De at this level of theory.