Electronic excitation of H2 by electron impact using soft norm-conserving pseudopotentials

We calculate electronic excitation cross sections for the b3Σ+u a3Σ+g c3Πu, and d3Πu states of H2 by electron impact. Our results were obtained with the Schwinger multichannel method with pseudopotentials and real potentials at the two-channel level of approximation. Pseudo-H atoms are used to generate H2 molecules with almost the same low-energy spectrum as the real molecules. We show that the dynamics of the electronic excitation process of the pseudomolecules by electron impact is very similar to the real case. Our results support the idea that pseudopotentials can be used to obtain reliable molecular electronic excitation cross sections by low-energy electron impact, confirming the expectations of previous studies with CH2O [Bettega et al., Phys. Rev. A 25, 1111 (1993)] and HBr [Rescigno, J. Chem. Phys. 104, 125 (1996)]. copyright 1996 The American Physical Society