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

Abstract

Energy levels, normal and specific mass shift parameters as well as electronic densities at the nucleus are reported for numerous states along the beryllium, boron, carbon, and nitrogen isoelectronic sequences. Combined with nuclear data, these electronic parameters can be used to determine values of level and transition isotope shifts. The calculation of the electronic parameters is done using first-order perturbation theory with relativistic configuration interaction wave functions that account for valence, core-valence and core-core correlation effects as zero-order functions. Results are compared with experimental and other theoretical values, when available.

Isotope shifts of the2p3/2−2p1/2transition in B-like ions

“…An independent evaluation of the non-QED mass shifts based on the multiconfiguration Dirac-Fock method was presented in Ref. [15]. For B-like argon the results of this calculation agree with those from Ref.…”

“…A small discrepancy of the non-QED part between the present work and Ref. [15] is within the uncertainty.…”

“…[15], where the formula (12) was employed, are presented in the last column. It can be seen that the calculations by formula (12) have a rather poor accuracy for heavy ions.…”

Hyperfine structures and Landé gJ-factors for n=2 states in beryllium-, boron-, carbon-, and nitrogen-like ions from

“…To monitor the convergence of the calculated energies and the physical quantities of interest, the active sets are increased in a systematic way by progressively adding layers of correlation orbitals. The configuration expansions strategies for the different ions, outlined in our previous work on isotope shifts [21] and included in the subsections below for the sake of completeness, were aimed at generating wave functions with high overall quality,…”

“…For this reason the calculations in this work rely instead on the fully relativistic grasp2k code [17,18], which has modules both for hyperfine structure [19] and Landé g J -factors [20]. The purpose of the present work is to complement the data sets on the isotope shift electronic factors [21] along the beryllium, boron, carbon, and nitrogen isoelectronic sequences with hyperfine interaction constants and Landé g J -factors. The values should also serve as reference for other theoretical work.…”