Cold and ultracold reactive collisions of Li with LiNa

The results of full-dimensional and numerically exact quantum reactive scattering calculations are presented for the Li + LiNa(v=0, j=0) → Li₂(v',j') + Na reaction. The calculations are based on an ab initio potential energy surface that includes an accurate treatment of the long-range dispersion interactions. Total and rotationally resolved rate coefficients are reported as a function of collision energy from 1 nK to 1 K. All contributing partial waves are included in the calculations at all energies. Several shape resonances (bumps) are observed in both the total and rotationally resolved rate coefficients within the cold energy regime. Of particular interest, the angular distributions of the scattered product states are also reported. The angular distributions exhibit significant quantum interference and resonance effects that lead to intriguing structure (i.e., spikes, ridges, bumps, and valleys) as a function of both collision energy and scattering angle. This structure is unique to each Li₂ product state and could be controlled and manipulated experimentally via the selection of a particular initial LiNa rovibrational state, stereodynamics, or external fields.