Large-scale relativistic configuration-interaction calculation of the3s21S0-3s3p1,3P1transition energies in magnesiumlike ions

Abstract

We have calculated the ${3\mathrm{s}}^{21}$${\mathrm{S}}_{0}$-${3\mathrm{s}3\mathrm{p}}^{1,3}$${\mathrm{P}}_{1}$ transition energies for neutral magnesium and Mg-like ${\mathrm{Ar}}^{6+}$, ${\mathrm{Cu}}^{17+}$, ${\mathrm{Kr}}^{24+}$, and ${\mathrm{Mo}}^{30+}$ using the relativistic configuration-interaction (CI) method. These calculations are based on the relativistic no-pair Hamiltonian which includes Coulomb and retarded Breit interactions and employ finite B-spline basis functions. Quantum electrodynamic and mass polarization corrections are also calculated. For Mg-like ions studied here, intravalence correlations are treated exactly by saturating the basis with all configurations that arise from valence-valence excitations. Contributions from core polarization are also calculated with large-scale CI expansions by including dominant configurations from core-valence excitations. Agreement between theory and experiment are good for all the Mg-like ions studied here.