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

• URL: http://arxiv.org/abs/2103.04923v1
• Date: Mon, 8 Mar 2021 17:35:21 GMT
• Title: All-order relativistic computations for atoms and molecules using an explicitly correlated Gaussian basis
• Authors: P\'eter Jeszenszki, D\'avid Ferenc, Edit M\'atyus
• Abstract summary: 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. The procedure is tested for nuclear charge numbers from $Z=1$ (hydrogen) to $28$ (iron)
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• 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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