Kaptein-Closs rules

{
  "id": "MLC-T-CHM-006304",
  "term": "Kaptein-Closs rules",
  "field": "Chemistry",
  "definition": "A set of qualitative rules that predict the sign, emission or enhanced absorption, of CIDNP signals in NMR spectra of products formed through radical pairs. For a net polarization the sign is the product of four factors: the spin multiplicity of the precursor, whether the product forms inside the radical cage or after escape, the sign of the g-factor difference between the two radicals, and the sign of the hyperfine coupling constant of the nucleus.",
  "subject": "Organic and Biomolecular Chemistry",
  "see_also": [
    "chemically induced dynamic nuclear polarization"
  ],
  "references": [
    "PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2250 (https://doi.org/10.1351/pac199668122223)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/kaptein-closs-rules/"
}