Relativistic semiempirical-core-potential calculations in Ca+, Sr+, and Ba+ ions on Lagrange meshes
Relativistic atomic structure calculations are carried out in alkaline-earth-metal ions using a semiempirical-core-potential approach. The systems are partitioned into frozen-core electrons and an active valence electron. The core orbitals are defined by a Dirac-Hartree-Fock calculation using the GRASP2K package. The valence electron is described by a Dirac-like Hamiltonian involving a core-p