Theoretical study on the formation of tetraoxygen conformational isomerism in the CO2 with O3 reaction

The reaction mechanism of CO2 with O3 on the singlet potential energy surface has been investigated at the CBS-QB3//B3LYP/6-311++G(3df, 3pd) level of theory. The reactants are initially associated with adducts IN1 (OOO–OCO) and IN2 (OC–cyclic O4) in a barrier-less process. Then, adducts undergo isomerization and dissociation processes to produce P1 (CO + 23O2) and P2 (CO3 + 3O2) with two different mechanisms. The calculated results show that there is no favorable pathway for the formation of these two products in the atmospheric reaction of CO2 with O3.