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Updated: Oct 25, 2025

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Variations of the Hartree-Fock fractional-spin error for one electron

Hugh G A Burton1, Clotilde Marut2, Timothy J Daas3

  • 1Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3QZ, United Kingdom.

The Journal of Chemical Physics
|August 8, 2021
PubMed
Summary

Fractional-spin errors in density functional approximations, like Hartree-Fock, are reduced in one-electron systems. Methods like unrestricted and generalized Hartree-Fock minimize these errors by localizing electrons or rotating spin coordinates.

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