Energy Distribution Among Reaction Products: H + SCl(2) ? HCl + SCl

The method of arrested relaxation has been applied to the study of infrared chemiluminescence arising from HCl(upsilon'>0) formed in the reaction H + SCl(2) ? HCI + SCl. The main findings are (a) that the mean fraction of the available energy entering vibration in the new bond is similar to that for the reaction H + Cl(2) ? HCl + Cl, the value being f (upsilon') approximately 0.43 (assuming the energy available for distribution among the products to be E'(tot) = 48 kcal mole(-1)); (b) that the breadth of the distribution over the populated vibrational levels, upsilon' = 1-5, substantially exceeds that for H + Cl(2) ? HCl + Cl, indicating altered reaction dynamics; (c) that the rotational distribution in the newly formed HCl is double-peaked, suggesting two distinct types of reaction dynamics (neither closely resembling that for H + Cl(2)), one of which gives rise to HCl with modest rotational excitation and one to HCl with a high degree of rotational excitation; (d) the mean fraction of E'(tot) entering product rotation (averaged over all reactive encounters) is f (R') asymptotically equal to 0.19; (e) the group of reactive encounters that result in less rotationally excited HCl are distinguished from the group that result in highly rotationally excited HCl, by differing correlation with upsilon'; this is further evidence that two distinct types of dynamics are involved in the reaction H + SCl(2) ? HCl + SCl.