Generalized Van Vleck perturbation theory study of chlorine monoxide
edited by: Theodore E. Simos, George Maroulis
The second order generalized Van Vleck perturbation (GVVPT2) variant of multireference perturbation theory for molecular electronic structure theory was used to study the ground and first excited states of the atmospherically important molecule chlorine monoxide (ClO). Unlike multiconfigurational self-consistent field (MCSCF) results, GVVPT2 shows that the A 2Π state has a local minimum, in agreement with experiment. This study supports the growing evidence that GVVPT2 can be used to study complex electronic structures, including those involving excited states and radicals.