Predicting new molecular species of potential interest to atmospheric chemistry: The isomers HSI and HIS

Structural, vibrational, and energetic properties of new molecular species, HSI and HIS are investigated for the first time using a state-of-the-art theoretical approach. These molecules can be easily differentiated by their geometric parameters and vibrational spectra. HSI is much more stable, and a direct unimolecular isomerization is very unlikely. Kinetics estimates predict that only at low temperatures there is a possibility of isolating HIS. For HS−I, we estimate a bond dissociation energy of 46.25 kcal/mol, and a heat of formation at 298.15 K of 12.84 kcal/mol. For the H2S + I2 → HSI + HI reaction enthalpy, we found 8.40 kcal/mol.