Regenbogenstreuung an Kalium-Quecksilber

Differential cross section measurements for the scattering of K by Hg at thermal energies are reported. Rainbow angles are compared with literature data and agreement within 2% is found. The data indicate a departure of the rainbow cross section from the Airy integral approximation. The measured variation of the rainbow angle with collision energy cannot safely be explained by those intermolecular potentials for which numerical calculations are available.