On the discrepancies of the calculated C5+(n=5) capture cross sections in C6+-H collisions

We present new results for electron transfer cross sections in C6+-H collis ions at low and intermediate impact energies (0.1-500 keV amu(-1)). The imp act parameter semiclassical method is used within the atomic-state close-co upling approach. Special attention is concentrated on the C5+(n = 5) captur e channels, for which severe discrepancies have been reported at low impact energies. We identify and discuss the mechanisms giving rise to the discre pancies in terms of avoided crossings in the molecular energy diagram. Traj ectory effects are also introduced with the use of channel-selective deflec tion patterns obtained by classical trajectory Monte Carlo calculations.