Inner-shell excitation energies, transition rates and autoionization rates of 2s2p2(4P)3d configuration in N II

Based on the Multi-Configuration Dirac-Hartree-Fock (MCDHF) method, accurate atomic spectra data including the transition rates, line strengths, and oscillator strengths for the inner-shell excitation configuration 2s2p²(⁴P)3d in N II ion are reported by taking into account the core-core, core-valence and valence correlation effects as well as the Breit interaction. Good accordance can be found in the comparison with other calculations and measurements. Because the highly excited 2s2p²(⁴P)3d configuration in N II is larger than the N III thresholds 2s²2p²P^o_3/2 and ²P^o_1/2 , there exists an autoionization phenomenon. Even the autoionization rates of 2s2p²(⁴P)3d are much larger than its radiative transition rates. This causes that the energy levels of 2s2p²(⁴P)3d configuration, especial for the triple states ³P, ³D and ³F, become considerably instable. In addition, there are strong energy level mixing among the 2s2p²(⁴P)3d configuration and the highly excited configurations 2s²2pnl (n = 6; l = p, f, h) with same even parity. These enable the energy levels and their transition rates become sensitive to core correlation effect and Breit interaction.