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arXiv · 2103.04923

All-order relativistic computations for atoms and molecules using an explicitly correlated Gaussian basis

Péter Jeszenszki·Dávid Ferenc·Edit Mátyus
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Abstract

A variational solution procedure is reported for the many-particle no-pair Dirac-Coulomb-Breit Hamiltonian aiming at a parts-per-billion (ppb) convergence of the atomic and molecular energies, described within the fixed nuclei approximation. The procedure is tested for nuclear charge numbers from $Z=1$ (hydrogen) to $28$ (iron). Already for the lowest $Z$ values, a significant difference is observed from leading-order Foldy-Woythusen perturbation theory, but the observed deviations are smaller than the estimated self-energy and vacuum polarization corrections.

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Péter Jeszenszki, Dávid Ferenc, Edit Mátyus. 2021-03-08. All-order relativistic computations for atoms and molecules using an explicitly correlated Gaussian basis. https://doi.org/10.1063/5.0051237

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