All-order explicitly correlated relativistic computations for atoms and molecules

Péter Jeszenszki; Dávid Ferenc; Edit Mátyus

doi:10.1063/5.0051237

All-order explicitly correlated relativistic computations for atoms and molecules

J Chem Phys. 2021 Jun 14;154(22):224110. doi: 10.1063/5.0051237.

Authors

Péter Jeszenszki¹, Dávid Ferenc¹, Edit Mátyus¹

Affiliation

¹ Institute of Chemistry, ELTE, Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest H-1117, Hungary.

PMID: 34241227
DOI: 10.1063/5.0051237

Abstract

A variational solution procedure is reported for the many-particle no-pair Dirac-Coulomb and Dirac-Coulomb-Breit Hamiltonians 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.