Abinitio MRD-CI study of NO2. 1. Multi-dimensional potential surfaces for the two lowest 2A′ states

Abstract

For a detailed theoretical abinitio study of the X2A1/A2B2 system of the NO2 molecule, three-dimensional potential energy surfaces have been calculated with the MRD-Cl method for both symmetric and asymmetric NO bond distances. The calculated data are given here together with the technical parameters of the respective treatment, and the main features of the surfaces are discussed. The geometrical locations and depths of the computed energy minima as well as the A–X vertical transition energy are found to be in good agreement with all known experimental data and allow for a good qualitative understanding of the overall appearance of the observed spectrum. The wavefunctions and potential energy surfaces will be used in subsequent investigations for the study of various molecular properties and coupling elements involved in the X2A1/A2B2 system of NO2.