TRANSLATIONAL ENERGY-RELEASE IN THE REACTION O(P-3)-]H+HSO(H2S)

O(P-3) 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 r eaction 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 a t 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 r eaction barrier imply that at least some energy will be left in the HS O radical. If the HSO product had an average of 3-4 kcal/mol of intern al energy, the ab initio theoretical value for Delta(f)H(0) degrees(HS O) near -5 kcal/mol would be confirmed. (C) 1997 Published by Elsevier Science B.V.