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Journal of Physics B Atomic Molecular and Optical Physics

Relativistic coupled-cluster calculation of hyperfine-structure constants of La 2+

Fang Li, Hong Ma, Yong-Bo Tang

Published Nov 25, 2020• 10 citations
Publisher

Abstract

Abstract Using the singles and doubles approximated relativistic coupled-cluster method, we calculate hyperfine-structure constant A and B of 24 low-lying states of La 2+ . The results of the lowest four states 5 d 3/2,5/2 and 4 f 5/2,7/2 are compared with recently measured values (Olmschenk et al 2017 Phys. Rev. A 96 032502). Reasonable agreement is found for hyperfine-structure constant A of 5 d 3/2 and 4 f 5/2,7/2 states, but the hyperfine-structure constant A of 5 d 5/2 and the hyperfine-structure constant B have a large deviation. To understand the role of the electron correlation effect, the intermediate results from lower-order many-body perturbation-theory and the linear version of coupled-cluster with single and double approximation are also presented. In the framework of coupled-cluster theory, the contribution trends from individual correlation effects are also investigated.

DOI
10.1088/1361-6455/abcdf0

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Investigating Role of Electron Correlation Effects via Triple Excitations for Precise Evaluation of Energies and Hyperfine Structure Constants in 23^{23}23Na
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We demonstrate an iterative scheme for coupled-cluster property calculations without truncating the dressed properties operator. For validation, magnetic dipole hyperfine constants of alkaline-earth-metal ions are calculated using relativistic coupled-cluster theory and the role of electron correlation is examined. Then a detailed analysis of the higher-order terms is carried out. Based on the results, we arrive at an optimal form of the dressed operator, which we recommend for properties calculations with relativistic coupled-cluster theory.