Observation of high frequency quantum oscillations in elastic differential cross sections: A critical test of the Ne–Ar interaction potential

The high frequency quantum oscillations superimposed on the falloff of the main rainbow structure have been clearly resolved in the elastic differential cross section for Ne–Ar at a collision energy of 65.5 meV. These new, high resolution data have allowed us to discriminate between two recently proposed multiproperty potentials for the Ne–Ar system, which only differ by a few percent in their range parameters. The data are found to be inconsistent with the predictions derived from the potential of Aziz and van Dalen [J. Chem. Phys. 81, 779 (1984)] (ε=5.96 meV, rm =3.414 Å, σ=3.068 Å) and confirm a previous potential by Candori et al. [Chem. Phys. Lett. 90, 202 (1982)] (ε=5.74 meV, rm =3.52 Å, σ=3.133 Å) in the whole attractive part and in the low repulsive region.