As a linear triatomic, centrosymmetric molecule composed of only second row elements, CO2 is one of the simplest polyatomic systems. CO2 attracts considerable interest from molecular spectroscopists and the broader scientific community as a well-known greenhouse gas with notable impacts on climate . Of particular relevance to the current work, the electronic structure of CO2 and its low-lying ionic states have been characterized by photoabsorption, photoionization, and photoelectron spectroscopy . The lowest four ionic states of CO2 are the