Theoretical study on the atmospheric formation of SOx (x = 1-3) in the SSO(1A′) and O2(3Σg-) reaction

The reaction pathways of SSO(1A′) with O2(3Σg-) on the closed-shell singlet potential energy surface have been investigated theoretically at the B3LYP/6-311++G(3df,3pd) level of computation. The calculated results show that SSO(1A′) and O2(3Σg-) directly transform to the intermediate SSO3(a) (1A) via TS1. Then, the intermediate SSO3(a)(1A) undergoes isomerization and dissociation processes to produce SO2(1A1) and SO(1Δ). There are two pathways for the product SO(1Δ). One pathway is relaxation of SO(1Δ) to SO(3Σ). The other one is the reaction of SO(1Δ) with O2(3Σg-) to produce SO3(D3h)(1A′). The cleavage and formation of the chemical bonds in the reaction pathways are discussed using the topological analysis of electronic density. The results show that three ring transition structure regions exist in the studied reaction.