Abstract
The total (integrated) cross section for the collision of an atom and a diatomic molecule (rigid rotor) is computed in the distorted‐wave Born approximation (DWBA) in order to see how information concerning the anisotropic potential can be obtained from such measurements. It is seen that the anisotropy parameters can be obtained most directly from the amplitude of the oscillatory contribution to the cross section. The frequency of the oscillations is determined by the velocity dependence of the rainbow angle of the spherically symmetric distorting potential and (to lowest order) contains no dependence on the anisotropy. Elastic and inelastic transitions are treated.