Spin projection

{
  "id": "MLC-T-CHM-011204",
  "term": "Spin projection",
  "field": "Chemistry",
  "definition": "A mathematical procedure used in quantum chemistry to remove spin contamination from a wavefunction that is not an eigenfunction of the total spin squared operator. This technique aims to restore the purity of the spin state, leading to more accurate energy calculations. It is often applied to unrestricted Hartree-Fock wavefunctions.",
  "subject": "Organic and Biomolecular Chemistry",
  "see_also": [
    "spin contamination"
  ],
  "references": [
    "PAC, 1999, 71, 1919. 'Glossary of terms used in theoretical organic chemistry' on page 1963 (https://doi.org/10.1351/pac199971101919)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/spin-projection/"
}