Alignment and orientation of atomic orbitals in Na(3p)+Na+interactions

Abstract
The authors use an efficient matrix propagator method to solve the coupled equations describing populations of the adiabatic states of Na2+ during a collision of Na+ with laser-excited Na(3p). Both straight-line and curved energy-conserving classical trajectories for the nuclei are used. Electronic motion is treated explicitly with a common translation factor. The radius at which the electronic angular momentum of a partially coherent mixture of Na(3p sigma u) and (3p pi u) becomes locked at the molecular axis is evaluated and the dependence of differential cross sections for inelastic transitions on the initial orbital alignment and orientation is discussed. The elementary mechanisms responsible for the observed effects are analysed numerically. Results are in qualitative agreement with recent experimental findings.