A theoretical calculation of atomic parameters for the transitions of Si II

Energy levels, wavelengths, transition probabilities, oscillator strengths and line strengths of transitions between computed levels are reported for Si II by using the multiconfiguration Dirac–Hartree–Fock method. The contributions of Breit interaction and quantum electrodynamics correction are taken into consideration. Comprehensive comparisons are made with available experimental and theoretical values, and the accuracy of the present results is assessed to be better than that of other values, which is much closer to the experimental values. The atomic structure parameters of some higher excited states that have no other theoretical values are also calculated and listed in this paper. We came to the conclusion that the contributions of Breit interaction and quantum electrodynamics correction cannot be ignored for high-precision excitation and transition energy calculations.