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arXiv · 2110.06647

On the Breit interaction in an explicitly correlated variational Dirac-Coulomb framework

Dávid Ferenc·Péter Jeszenszki·Edit Mátyus
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Abstract

The Breit interaction is implemented in the no-pair variational Dirac-Coulomb (DC) framework using an explicitly correlated Gaussian basis reported in the previous paper [Paper I: P. Jeszenszki, D. Ferenc, and E. M\'atyus (2022)]. Both a perturbative and a fully variational inclusion of the Breit term is considered. The no-pair DC plus perturbative Breit as well as the no-pair Dirac-Coulomb-Breit energies are compared with perturbation theory results including the Breit-Pauli Hamiltonian and leading-order non-radiative quantum electrodynamics corrections for low $Z$ values. Possible reasons for the observed deviations are discussed.

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Dávid Ferenc, Péter Jeszenszki, Edit Mátyus. 2021-10-13. On the Breit interaction in an explicitly correlated variational Dirac-Coulomb framework. https://doi.org/10.1063/5.0075097

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