Translational energy release in the reaction O(3P) + H2S → H + HSO

O(3P) atoms were generated by photodissociating NO2 at 351 and 308 nm in the presence of H2S. The average kinetic energy of the H and HSO reaction products is 9.4 ± 0.6 and 12.0 ± 0.7 kcal/mol respectively. These values are consistent with a value for the heat of formation at 0 K of HSO of − 1 kcal/mol only if the HSO product is internally cold. The elongated SO bond in the theoretical transition state and the reaction barrier imply that at least some energy will be left in the HSO radical. If the HSO product had an average of 3–4 kcal/mol of internal energy, the ab initio theoretical value for ΔfHo°(HSO) near −5 kcal/mol would be confirmed.