The Radiative Association of Li + and H, Li and H +, and Li and H

The rate coefficients for formation of LiH⁺ and LiH by radiative association are determined for temperatures between 50 and 5000 K by quantum mechanical methods. The rate coefficients generally decrease slowly with temperature and have magnitudes at 300 K of 7.5 × 10⁻²³, 3.3 × 10⁻¹⁵, and 3.3 × 10⁻² cm³ s⁻¹ for Li⁺ + H, Li + H⁺, and Li + H, respectively. Radiative association cross sections and ab initio potentials and dipole moments for the ground and 2²Σ⁺ states of LiH⁺ are also given. We briefly discuss the importance of these formation rates for the lithium chemistry of the early universe.