Associative Ionization in Slow Collisions between Atoms. II

Associative ionization between atoms in slow collisions A * + B → A B + + e is investigated theoretically for the case in which the excitation energy of A * is smaller than the ionization potential of B . Two cases are considered. First, on the basis of the adiabatic or diabatic representation, a general treatment is described for the case involving a potential curve crossing. In the second case of no potential curve crossing the cross section formula is presented which does not require numerical differentiations and thus is of practical usefulness. A rough estimate of the energy dependence of the cross section is also discussed in this case. Some qualitative applications to a hydrogen system are made.