Collision-Energy Dependent Stereodynamics of Dissociative Charge Exchange Reaction between Ar⁺ and CO

Long-distance charge-dipole attraction between atomic ion and randomly oriented polar molecule potentially makes the molecular orientation, which profoundly influences the products' kinetics of collisional reaction. Using the three-dimensional ion velocity map imaging technique, here we report a collision-energy dependent stereodynamics of dissociative charge exchange reaction Ar⁺ + CO → Ar + O + C⁺ in a range of 7.46-9.97 eV. At the lowest collision energy, the most C⁺ products are forward-scattered and are along the collision axis and are attributed to three different dissociation channels including the predominant one experiencing the rotating intermediate ArC⁺. At the high collision energies, the remarkably diffusive distribution of C⁺ arises from the prompt dissociation of the rebounded CO⁺. The different dynamic processes arising from the nearly collinear collision are elaborated explicitly on the basis of the data analyses using the Doppler kinetics models.