Accurate line strengths, transition rates, and lifetimes of 2s2p(2)(P-4)3s in NII

Accurate line strengths, transition rates, oscillator strengths, and lifetimes from the inner-shell 2s2p(2)(P-4)3s states P-5 and P-3 of Nii are reported within the framework of the multiconfiguration Dirac-Hartree-Fock method. The effects of core-core, core-valence, and valence correlations; the Breit interaction; and the quantum electrodynamics effect are taken into account. Through investigating the influences of electron correlation effects on the quintet states, it is found that the core-correlation effect has a certain compensation effect in accurately optimizing the line strengths, transition rates, and lifetimes of quintet states; the branching fractions of 2s2p(3) S-5(2)degrees-2s2p(2)(P-4)3s P-5(1, 2, 3) tend to 1, which is inferred as a peculiar intrinsic property that can be useful for plasma diagnostics; unlike P-3(0, 1, 2) and P-5(1, 3), the calculations of lifetime of P-5(2) show some J dependence, and the velocity form calculations for this J = 2 dependence are much more sensitive to electron correlations of 1s(2)2s2p(2)(P-4)3l (l = p, d) than those in the length gauge, which will be helpful to deal with the calculations of lifetime with J= 2 dependence in the carbon-like isoelectronic series.