CENTRIFUGAL-SUDDEN HYPERSPHERICAL STUDY OF CL-]CLH+CL REACTION DYNAMICS ON TIGHT-BEND AND LOOSE-BEND POTENTIAL-ENERGY SURFACES(HCL)

A centrifugal-sudden hyperspherical (CSH) quantum calculation has been carried out for the three-dimensional reaction Cl + HCl --> ClH + Cl, using the extended London-Eyring-Polanyi-Sato (LEPS) potential energy surface no. 3 of Persky and Komweitz (PK3), which is an example of a 'tight-bend' surface, Quantities calculated include: state-to-state an d cumulative reaction probabilities, and differential and integral cro ss sections. Comparison is made with CSH results from the 'loose-bend' LEPS surface of Bondi-Connor-Manz-Romelt (BCMR). Three simple models are used to understand qualitatively trends in the computed results fr om the PK3 and BCMR surfaces: (1) a classical hard-sphere model, which describes collisions of the reactants, (2) a J shift approximation fo r the reaction probabilities, where J is the total angular momentum qu antum number, (3) a semi-classical optical model for the reactive diff erential cross sections. In addition, the angular distributions are an alysed by an (asymptotic) nearside-farside (NF) theory in order to ext ract their physical content. The NF analysis shows that high frequency oscillations in the forward-angle scattering are an interference effe ct caused by a resonance.