Inversion of orbiting scattering from elastic collisions of reactive molecules

Abstract

For elastic scattering produced by an attractive, spherically symmetric potential, the classical deflection angle is a single‐valued function for impact parameters equal to or greater than that which gives orbiting at the centrifugal barrier. If reaction removes contributions from smaller impact parameters, the potential in this outer region can be derived from the elastic scattering by a simple inversion procedure. This is obtained by slightly modifying the Firsov method, so as to integrate from small angles inwards. Close to the centrifugal barrier, the scattering is determined primarily by the first and second derivatives of the potential, and an approximate inversion method for obtaining the derivatives is also given. These procedures are applied to data for nonreactive scattering of K atoms from Cl₂, Br₂, I₂, and ICl. The results indicate the orbiting model is a useful approximation for such reactions in the thermal range, although a less simple treatment is necessary at higher energies. The potential parameters obtained are discussed in terms of the ’’electron‐jump’’ mechanism for these reactions and are related to other models and experiments.