IMPROVEMENT IN FIRST BORN THEORY OF ELECTRON SCATTERING BY MOLECULAR SYSTEMS .2. EXAMPLE OF 1SSIGMAG-2PSIGMAU TRANSITION IN H+2

The asymptotic closure cross section, derived in I of this series, is calculated for the 1sg-2pu excitation of H2+ by fast electrons. These data are compared with earlier treatments of this system which were based on a less rigorous theory. The earlier data are observed to be surprisingly accurate. The Bethe cross section for exciting discrete vibrational modes in the 2pu orbital of H2+ is calculated. This cross section is then used, along with the asymptotic closure cross section, to generate the Bethe cross section for all continuum modes of nuclear motion in the 2pu orbital of H2+. Two approximations are considered for this partitioning of the asymptotic closure cross section and they are not found to be, in general, very useful. © 1969 The American Physical Society.