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

Dávid Ferenc; Péter Jeszenszki; Edit Mátyus

doi:10.1063/5.0075097

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

J Chem Phys. 2022 Feb 28;156(8):084110. doi: 10.1063/5.0075097.

Authors

Dávid Ferenc¹, Péter Jeszenszki¹, Edit Mátyus¹

Affiliation

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

PMID: 35232200
DOI: 10.1063/5.0075097

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 [P. Jeszenszki, D. Ferenc, and E. Mátyus, J. Chem. Phys. 156, 084111 (2022)]. Both a perturbative and a fully variational inclusion of the Breit term are considered. The no-pair DC plus perturbative Breit and the no-pair DC-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.