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DOE OSTI · 2419710

Correlated Dirac–Coulomb–Breit multiconfigurational self-consistent-field methods

Hoyer, Chad E.·Lu, Lixin·Hu, Hang·Shumilov, Kirill D.·Sun, Shichao·Knecht, Stefan·Li, Xiaosong
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Abstract

The fully correlated frequency-independent Dirac–Coulomb–Breit Hamiltonian provides the most accurate description of electron–electron interaction before going to a genuine relativistic quantum electrodynamics theory of many-electron systems. In this work, we introduce a correlated Dirac–Coulomb–Breit multiconfigurational self-consistent-field method within the frameworks of complete active space and density matrix renormalization group. In this approach, the Dirac–Coulomb–Breit Hamiltonian is included variationally in both the mean-field and correlated electron treatment. Here, we also analyze the importance of the Breit operator in electron correlation and the rotation between the positive- and negative-orbital space in the no-virtual-pair approximation. Atomic fine-structure splittings and lanthanide contraction in diatomic fluorides are used as benchmark studies to understand the contribution from the Breit correlation.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYAtomic fine structureChemistryComplete-active space self-consistent fieldCorrelated electronsDensity matrix renormalization groupDirac relativistic electron equationDirac-Coulomb-Breit HamiltonianElectronic correlationMany electron systemsMulti-configurational self-consistent fieldPhysics

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Hoyer, Chad E., Lu, Lixin, Hu, Hang, Shumilov, Kirill D., Sun, Shichao, Knecht, Stefan, Li, Xiaosong. 2023-01-23. Correlated Dirac–Coulomb–Breit multiconfigurational self-consistent-field methods. https://doi.org/10.1063/5.0133741

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