Classical ionization and charge-transfer cross sections for ${\mathrm{H}}^{+}$ + He and ${\mathrm{H}}^{+}$ + ${\mathrm{Li}}^{+}$ collisions with consideration of model interactions

The three-body system is analyzed in relation to the calculation of atomic scattering cross sections. A method is presented to generate the initial electronic conditions for the classical-trajectory Monte Carlo method in the case where the active electron is subject to non-Coulomb interactions. The method is then applied to study the collisions of ${\mathrm{H}}^{+}$ with He and ${\mathrm{Li}}^{+}$ targets in the intermediate- to high-energy range. Single-electron capture and single-ionization total cross sections are presented for both collision systems. In the case of He targets, total cross sections for double ionization and singly differential cross sections for free-electron production are also calculated. Cross sections and initial electronic distributions are obtained with both Coulomb and model interactions and compared. Good agreement is found between theoretical and experimental results, except for the double ionization of He.