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Breit interaction contribution to parity violating potentials in chiral molecules containing light nuclei
1Frankfurt Institute for Advanced Studies, Johann Wolfgang Goethe-University Frankfurt am Main, Ruth-Moufang-Str. 1, D-60438 Frankfurt am Main, Germany. r.berger@fias.uni-frankfurt.de
The Journal of Chemical Physics
|December 3, 2008
Summary
The Breit interaction is crucial for predicting parity violation in enantiomers. Neglecting its spin-other-orbit coupling term causes significant errors, highlighting its importance in electroweak quantum chemistry.
Area of Science:
- Quantum Chemistry
- Relativistic Effects
- Molecular Interactions
Background:
- Parity violation is key for enantiomer differentiation.
- Breit interaction includes orbit-orbit, spin-spin, and spin-other-orbit couplings.
- Accurate prediction of parity violating potentials (V(pv)) is computationally challenging.
Purpose of the Study:
- To investigate the significance of the Breit interaction for V(pv) calculations.
- To identify the primary source of discrepancies in V(pv) predictions.
- To analyze relativistic effects in heavier molecules.
Main Methods:
- Electroweak quantum chemical frameworks.
- Four-component Dirac-Hartree-Fock-Coulomb (DHFC) calculations.
- One-component Hartree-Fock (HF) calculations with relativistic enhancement factors.
Main Results:
- Neglecting the spin-other-orbit coupling term of the Breit interaction causes ~10% deviation in V(pv) for H(2)O(2).
- Further relativistic corrections in DHFC are <5%.
- The spin-other-orbit term's relative contribution to V(pv) decreases with nuclear charge in heavier homologs.
Conclusions:
- The Breit interaction, specifically its spin-other-orbit term, is essential for accurate V(pv) predictions.
- Discrepancies in H(2)O(2) V(pv) stem from neglecting the Breit contribution.
- Relativistic influences on V(pv) in heavier molecules can be approximated using relativistic enhancement factors.
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