Abstract
The radiative association processes originating in the 1(3)Pi continuum of the He (2(3)P)+ Li+ collisional system are investigated in this study. The calculations of the dynamic collision processes are based on highly accurate state-of-the-art ab initio calculations of the potential energy functions for the 1(3)Pi and the three lowest (3)Sigma states of HeLi+ and the associated transition dipole-moment functions.
Cross-sections for the spontaneous and stimulated radiative association processes are calculated as functions of collision energy. The corresponding rate coefficients characterizing the efficiency of the formation of the molecular ion in its a(3)Sigma(+), b(3)Sigma(+), and c(3)Sigma(+) states from the initial 1(3)Pi state are obtained over a wide range of temperatures.
At very low temperatures the 1 -> b process has a maximum rate-coefficient value of about 7.9 x 10(-13) cm(3) s(-1), whereas process 1 -> a reaches its maximum value of 2.0 x 10(-13) cm(3) s(-1) at a temperature of about 500 K. Altogether the three radiative association processes investigated here can be considered as the continuum-to-bound state radiative transition part of the total quenching of the initial collision channel.