The level structure of singly-ionized actinium

We have presented a multiconfiguration Dirac-Fock (MCDF) study in the framework of Breit and quantum electrodynamic (QED) effects on the low-lying level structure of singly-ionized actinium (Ac II). The computations have been carried out for 16 even- and 40 odd-parity levels. Excitation energies and electric dipole transition parameters, such as wavelengths, oscillator strengths and transition probabilities (or rates), for these low-lying levels have been reported. Results obtained have been compared with other available works in the literature.