The B2Σ interaction potential for Na---Ne determined from [Pi]---[Sigma] interference structures in differential scattering cross sections

Abstract

We have measured the differential cross sections for scattering of laser-excited Na(32P3/2) from Ne at thermal collision energies. For the interpretation of the experimental data we performed semi-classical calculations in which spin-rotational effects were taken into account. From the observed Π---Σ interference structures in the scattering cross sections we extracted detailed information about the A2Π and B2Σ interaction potentials. We found the excited-state potentials to be in excellent agreement with the potentials determined in recent spectroscopic work. The repulsive branch of the B2Σ potential could be accurately determined. An extrapolation with a Lennard-Jones (8,6) potential shape yielded an equilibrium distance rm = 15.1 ± 0.4 au. By comparing calculated differential cross sections based on model potentials with our experimental data we conclude that the model potentials of Peach are the most reliable theoretical Na*---Ne potentials known today.