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arXiv · 0902.4307

High-accuracy Complete Active Space multiconfiguration Dirac-Hartree-Fock calculations of hyperfine structure constants of the gold atom

Jacek Bierón·Charlotte Froese Fischer·Paul Indelicato·Per Jönsson·Pekka Pyykkö
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Abstract

The multiconfiguration Dirac-Hartree-Fock (MCDHF) model has been employed to calculate the expectation values for the hyperfine splittings of the 5d96s2 2D3/2 and 5d96s2 2D5/2 levels of atomic gold. One-, two-, and three-body electron correlation effects involving all 79 electrons have been included in a systematic manner. The approximation employed in this study is equivalent to a Complete Active Space (CAS) approach. Calculated electric field gradients, together with experimental values of the electric quadrupole hyperfine structure constants, allow us to extract a nuclear electric quadrupole moment Q(197Au)=521.5(5.0) mb.

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Jacek Bierón, Charlotte Froese Fischer, Paul Indelicato, Per Jönsson, Pekka Pyykkö. 2009-04-07. High-accuracy Complete Active Space multiconfiguration Dirac-Hartree-Fock calculations of hyperfine structure constants of the gold atom. https://doi.org/10.1103/physreva.79.052502

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