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Published on: April 24, 2014
Photochemistry of HOSO radical in the gas phase
Tarek Trabelsi1, Josep M Anglada2, Manuel F Ruiz-López3
1Department of Earth and Environment Science, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6243, USA.
Abstract:
The photochemistry of HOSO in the near- and deep-UV spectral range has been studied in the gas phase using the multireference configuration interaction MRCI+Q/aug-cc-pV(T+d)Z level of theory. HOSO is found to be a nonplanar radical in its ground electronic state with a torsion angle calculated to be 49.7°. The lowest three doublet electronic states are characterized by a large transition dipole moment and are implicated in the photodissociation of HOSO in the gas phase to generate SO and OH as products. Sulfur dioxide and hydrogen products may also result after UV absorption to reach the first excited state, and this channel competes with the production of OH and SO.
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