Random-phase approximation with exchange for the inner-shell electron transitions

We present our recently developed random-phase approximation with exchange (RPAE) method, which can be used to study the inner-shell electron transition in an open-shell atom. The expressions for the matrix elements of all terms of the dipole and Coulomb interactions have been derived and implemented in a computer program. The photoionization cross sections of the 4d giant resonances of Xe+, I, and I+ have been calculated. The results for Xe+ and I+ agree very well with the experimental data. However, the theoretical results for the I 4d cross section are still almost three to four times higher than the experimental data. We recommend a remeasurement of the I 4d giant resonance with a careful experimental arrangement.