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arXiv · 2006.16889

Diagonal and off-diagonal hyperfine structure matrix elements in KCs within the relativistic Fock space coupled cluster theory

Alexander V. Oleynichenko·Leonid V. Skripnikov·Andrei Zaitsevskii·Ephraim Eliav·Vladimir M. Shabaev
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Abstract

The four-component relativistic Fock space coupled cluster method is used to describe the magnetic hyperfine interaction in low-lying electronic states of the KCs molecule. Both diagonal and off-diagonal matrix elements as functions of the internuclear separation $R$ are calculated within the finite-field scheme. The resulting matrix elements exhibit very weak dependence on $R$ for the separations exceeding 8 Å, whereas in the vicinity of the ground-state equilibrium the deviation of molecular HFS matrix elements from the atomic values reaches 15\%. The dependence of the computed HFS couplings on the level of core correlation treatment is discussed.

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Alexander V. Oleynichenko, Leonid V. Skripnikov, Andrei Zaitsevskii, Ephraim Eliav, Vladimir M. Shabaev. 2020-06-30. Diagonal and off-diagonal hyperfine structure matrix elements in KCs within the relativistic Fock space coupled cluster theory. https://doi.org/10.1016/j.cplett.2020.137825

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