The Rydberg states of NO2: Vibrational autoionization of the nd sigma states

Ab initio configuration interaction calculations were carried out on the po tential-energy surfaces of the ground and Rydberg excited electronic states of NO2. The results show that potential-energy curves with typically Rydbe rg form are obtained for most of the excited states at linear geometries, s imilar to the ground-state potential of NO2+. At nonlinear geometries valen ce-Rydberg interactions complicate the potential-energy surfaces of the exc ited states. Quantum defect functions have been determined from the ab init io results on the 3d sigma Rydberg state and vibrational autoionization wid ths have been calculated for excited vibrational levels of members of the n d sigma series. (C) 2001 American Institute of Physics.