Radiative charge transfer and association in slow Li−+ H collisions

Abstract

Aims. The radiative charge transfer and association processes in Li − + H collisions are studied in the 10 -10 −10 eV center-of-mass energy range. Methods. we carried out total and ν -resolved state-selective cross sections have been carried out by using the fully quantum, optical potential, and semiclassical methods. Results. In the energy region below ~ 0.8 eV, the radiative association process is the dominant decay channel, while radiative charge transfer dominates at higher energies. Rich resonance structures are observed in the cross sections of both processes in the 0.1−1.5 eV energy range; These structures are associated with the quasi-bound states below the top of the centrifugal barrier of the effective potential in the entrance channel for specific vibrational and angular momentum states. It is found that with the increase of collision energy, the resonances occur for higher angular momentum states and lower vibrational states. Besides the cross sections for the studied processes we also present their reaction rate coefficients in the 10 -6 –10 6 K temperature range.