Offsetting the difficulties of the molecular model of atomic collisions in the intermediate velocity range

To offset the defective behavior of the molecular method of atomic collisions at intermediate energies, we propose a method to approximate the probability flux towards continuum and discrete states not included in the molecular basis. We check the degree of accuracy and limitations of the method for a model case where transition probabilities can be calculated exactly. An application to the benchmark case of ${\mathrm{He}}^{+}$+${\mathrm{H}}^{+}$ collisions is also presented, and yields complementary information on the properties of this approach.