Relativistic configuration interaction calculations of energy levels, isotope shifts, hyperfine structures, and transition rates in the 2s²2p²–2s2p³transition array for the carbon-like sequence

Abstract

Energy levels, fine-structure separations, specific mass shift parameters, isotope shifts, hyperfine interaction constants, Landé g J -factors and transition probabilities are reported for the 2s 2 2p 2 -2s2p 3 transition array in N II, O III, F IV, Ne V and Ti XVII. Wavefunctions were determined using the multiconfiguration Dirac-Hartree-Fock method with account for valence, core-valence and core-core correlation effects. The transition energies and rates are compared with experimental data and with values from other calculations.

Isotope shifts in beryllium-, boron-, carbon-, and nitrogen-like ions from relativistic configuration interaction calculations

“…Table 10 displays the total and excitation energies, the K NMS and K SMS parameters as well as the electronic F field shift factors for several levels of C-like ions (7 ≤ Z ≤ 28). Table 11 presents the comparison with Jönsson and Bieroń's results [53] who calculated the uncorrected K 1 SMS parameters. For each of the five ions considered in [53] (N II, O III, F IV, Ne V and Ti XVII), the K 1 SMS values are compared with each other, and with the corrected K SMS values evaluated in the present work (third column).…”

“…Table 11 presents the comparison with Jönsson and Bieroń's results [53] who calculated the uncorrected K 1 SMS parameters. For each of the five ions considered in [53] (N II, O III, F IV, Ne V and Ti XVII), the K 1 SMS values are compared with each other, and with the corrected K SMS values evaluated in the present work (third column). The small difference between the K 1 SMS values is due to differences in the optimization strategy.…”

“…. [53] This work [53] This work [53] This work Level Table 13 Total energies (in E h ), excitation energies (in cm −1 ), normal and specific mass shift K parameters (in GHz u), F field shift factors (in GHz/fm 2 ) for levels in the nitrogen isoelectronic sequence (7 ≤ Z ≤ 36 and Z = 42, 74). For each of the many-electron wave functions, the leading components are given in the LSJ coupling scheme.…”

Relativistic effects on the hyperfine structures of2p4(3P)3p2Do,<

“…Core-orbital contraction and charge density rearrangement due to relativity can be very important [57] and are a priori poorly described in the MCHF-BP approximation [42]. For fluorine however, the hyperfine structure parameters estimated with the MCHF-BP method are nicely coherent with the results obtained from the fully relativistic MCDHF method, suggesting that the orbital contraction effects are minor in comparison to the LS term relativistic mixing.…”

“…The coupled-cluster theory is promising [29][30][31] but investigation of hyperfine structures in more complex systems remains scarce [32]. Although further developments might be expected [33][34][35][36], the traditional multi-configuration methods combined with configuration interaction in their non relativistic [14,37,38] and relativistic [39][40][41][42][43] versions keep a respectable place in the ranking of ab initio methods for hyperfine structures calculations.…”