Atomic many-body theory methods are used to calculate the fine structure of negative ions formed by binding a p electron into an open shell, Ca-, Sr-, Ba-, and Ra-. This binding is due to a strong correlation potential acting between the electron and the neutral atom. Comparison with experimental data shows that the second order many-body perturbation theory calculation overestimates the correlation potential by 10% to 15%. Scaling factors are introduced in the correlation potential to reproduce experimental binding energies of the lower p1/2 components. This procedure yields fine-structure intervals in excellent agreement with experiment for Ca-, Sr-, and Ba-, and allows us to predict that in Ra- the p1/2 state is bound by 100 meV, and p3/2 is a resonance at 16 meV in the continuum.
|Physical Review A (Atomic, Molecular, and Optical Physics)
|Published - 01 Mar 1997