Partial photoionization cross section and photoelectron angular distribution for the X 2Σg+ state of N2+ in the static-exchange approximation

Abstract

The partial photoionization cross section of N2 leading to the production of N2+ in its X 2Σg+ ground state is calculated in the single-center frozen core static-exchange approximation. The initial and final states are antisymmetrized products using SCF molecular orbitals of either N2 or N2+ ground states. All these calculations reproduce well the σu shape resonance in the partial cross section. The photoelectron angular distribution is also calculated and the average over the vibrational motion is performed. The R-averaged results are in agreement with recent measurements using synchrotron radiation. The branching ratio of the cross sections leading N2+ in its two lowest vibrational states compares rather well with the experimental values obtained recently by West et al.