Multi-channel coupling effects for electronic excitations leading to the b3Σu+, a3Σg+, and c3Πu states of H2

In this work we use the unitarized distorted wave method to study the effect of multi-channel coupling on the calculated electronic excitation cross sections in H-2. Specifically, such an effect for electronic excitations leading to the excited states b(3)E(u)(+), a(3)Sigma(+)(g), and c(3)Pi(u) for incident energies varying from 15 to 60 eV is studied. Our results have shown that converged cross sections can be obtained with the inclusion of only triplet intermediate states, except for energies near the excitation thresholds, where the inclusion of singlet intermediate states is important. Also, convergence improves with increasing energies for all excitations considered. Comparison of our calculated cross sections with available experimental and other theoretical results is encouraging. (C) 2006 Wiley Periodicals, Inc.