Dynamics of two-stage direct three-body recombination of ions

► Direct recombination of Cs cation and Br anion in the presence of Xe is studied. ► Quasiclassical trajectory method is employed on a reliable PES. ► The ion closest approach and energy removal by Xe are separated by a varied time lag. ► In this general new two-stage model we propose, any stage can occur first. ► A one-stage process with zero lag and a delay of Xe exhibit quite different dynamics.