IOSA investigations of the effects of potential surface topography upon elastic and inelastic scattering and rotational relaxation in the (He, CO2) system

The effect of potential surface topography upon elastic and inelastic scattering has been investigated using the infinite‐order sudden approximation (IOSA) to compute total differential and integral cross sections, state‐to‐state cross sections, and the relaxation rates of depleted levels in the (He, CO2) and (3He, CO2) rigid rotor systems on six different potential energy surfaces that include three surfaces obtained from electrom–gas type calculations, two ab initio SCF surfaces, and one surface (KPK) obtained by empirical fitting to the measured total differential cross section. It is found that the total elastic, inelastic, and differential cross sections are very sensitive to the long‐range attractive terms in the potential, and the differential cross sections are also found to be significantly dependent upon the topography of the repulsive regions of the surface. Consequently, differential cross sections are very sensitive probes of surface topography and should be the data of choice for purpose of ...

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