Multiconfiguration calculations of electronic isotope-shift factors in Zn i

Abstract

The present work reports results from systematic multiconfiguration Dirac-Hartree-Fock calculations of electronic isotope-shift factors for a set of transitions between low-lying states in neutral zinc. These electronic quantities, together with observed isotope shifts between different pairs of isotopes, provide the changes in mean-square charge radii of the atomic nuclei. Within this computational approach, different models for electron correlation are explored in a systematic way to determine a reliable computational strategy and to estimate theoretical error bars of the isotope-shift factors.

MCDHF calculations of isotope shifts in neutral antimony

“…In the present paper, following previous IS studies [9,10] , we have used the fully relativistic multiconfiguration Dirac-Hartree-Fock (MCDHF) method [11] to calculate the IS electronic parameters, K RNMS , K RSMS and F , for 49 fine-structure levels belonging to the configurations 5s 2 5p 3 , 5s 2 5p 2 6s, 5s 2 5p 2 6p and 5s 2 5p 2 7p in Sb I. These parameters can be used to determine IS of the transitions involving these levels for any pair of Sb isotopes along with their different NMS, SMS and FS contributions or the corresponding changes in mean-square nuclear charge radius δ r 2 A,A .…”

“…30 fm. The field shift electronic factors (10) have been estimated in the first-order perturbation approximation using the electron wave function calculated for the reference isotope A = 121 using the prescriptions of Nazé et al [12] .…”

Electronic isotope shift factors for the Ir 5d76s24F9/2Schiffmann1, Godefroid2 2021Journal of Quantitative Spectroscopy and Radiative TransferSelf Cite6100View full textAdd to dashboardCite

“…as it was done [14][15][16][17] using the RIS3 program [18] designed as a module of the Grasp2K atomic structure package [19] .…”

“…Note also that the number of CSFs is growing significantly faster for the odd parity (around 1 150 0 0 0 CSFs) than for the even parity (around 150 0 0 0 CSFs), which might lead to an unbalanced treatment of electron correlation, and therefore a transition energy in poor agreement with experiments. Finally, S substitutions from the 4 f , 5 s and 5 p orbitals to the { 5 d, 6 s, 6 p} 5 i =1 L i active set of orbitals are included, as S substitutions play an important role, due to the one-body structure of the field shift operator [15] . Moreover, they are usually computationally 'cheap' as the number of CSFs generated is small compared to e.g., D substitutions.…”

Ab initio calculations of the hyperfine structure of zinc and evaluation of the nuclear quadrupole moment Q(Zn67)

“…The VV correlation model only allows SD substitutions from valence orbitals, while the VV+CV correlation model considers SrD substitutions from core and valence orbitals, limiting the substitutions to a maximum of one hole in the core. Oppositely to Filippin et al [48], core correlation is included in the final step through a configuration interaction calculation based on SD-SR expansions. The corrections for triple excitations estimated in section IV B (see Table V), are added in the very final step.…”