Total Absorption Cross Section for UV Excitation of Sulfur Monoxide

In a new study on sulfur monoxide, new
ab initio potential energy curves are developed for excited states
A3Π, B3Σ–, C3Π, and C′3Π and for three states
that are unassigned in the literature, which we numerically name 33Σ–, 43Π, and 53Π. All these excited states have allowed transitions
from ground state, X3Σ–. The ab
initio calculations were performed using the MRCI-F12+Q/aug-cc-pV­(5+d)­Z
level of theory implemented in MOLPRO2015. On the basis of close-coupling
R-matrix theory, fine structure absorption cross sections of isotopically
substituted sulfur monoxide are calculated for wavelengths of 190–300
nm. The spectra are shown at the highest possible resolution (FWHH
≈ 0.15–0.18 cm–1) for reference and
future studies. The effects of self-shielding and possible mutual
shielding are discussed.