Interaction Potentials from the Velocity Dependence of Total Atom-Atom Scattering Cross Sections

Abstract

Abstract : The velocity (V) dependence of the total cross section (Q) was previously measured for the scattering of lithium by all the rare gases and for potassium by krypton and xenon. Assuming a Lennard-Jones potential, the depth of the interatomic potential well, epsilon and the interatomic separation at the zero of potential energy, sigma was obtained from these measurements. From the experimental epsilon and sigma, a theoretical Q(V) was computed using a partial wave analysis. Good agreement with the experimental data was obtained. In this paper, K-Kr and Li-He are discussed which were studied in the 'low' velocity region and in the ''high'' velocity region, respectively. It is shown that epsilon and sigma may be unambiguously determined in the low-velocity region. In the highvelocity region such a determination requires precision which is unattainable with the experimental arrangement. (Author)