Relativistic calculations of the fine-structure intervals of the terms and the ionization energies of the , and ions

We report new calculations of the energy differences between the and levels of the , and ions; here n = 4, 5 and 6 for , and , respectively. The electron affinities of Ca, Ba and Sr have also been calculated. All estimates were obtained by performing a series of multiconfiguration Dirac - Fock calculations for the neutral atoms and their anions. Correlations among valence electrons in both the ground and excited states were included in these calculations. Our estimate of the fine structure of the ground state of is in good agreement with recent measurements. Our estimates of the electron affinities of Ca, Sr and Ba are in reasonable agreement with experiment.