Absorption spectra of SO + in the ultraviolet region

The potential energy curves (PECs), transition dipole moments (TDMs), spectroscopic constants, and spin–orbit coupling (SOC) matrix elements for eight doublet states (X 2 Π, A 2 Π, 1 2 Φ, C 2 Π, 1 2 ∆, B 2 Σ − , 1 2 Σ + , and 2 2 Σ + ) and two quartet states (a 4 Π and b 4 Σ − ) of the sulfur monoxide cation were calculated using the multireference configuration interaction (MRCI) method. Furthermore, the PECs of the X 2 Π and A 2 Π states were refined by fitting to the experimentally measured vibrational energy levels. Based on these data, the absorption cross sections arising from the A 2 Π-X 2 Π transition within the 30 000-50 000 cm − 1 range were simulated, and a comprehensive spectral analysis was performed. Moreover, the absorption cross sections for a total of six transitions - A 2 Π-X 2 Π, B 2 Σ − -X 2 Π, C 2 Π-X 2 Π, 2 2 Σ + -X 2 Π, 1 2 Σ + -X 2 Π, and 1 2 ∆-X 2 Π - were computed to simulate the absorption spectra of SO + in cosmic atmospheres. It is expected that the spectroscopic data presented in this work will facilitate the characterization of exoplanet atmospheres in future observational missions.