Secondary isotope effect

{
  "id": "MLC-T-CHM-010616",
  "term": "Secondary isotope effect",
  "field": "Chemistry",
  "definition": "An isotope effect observed when isotopic substitution occurs at a position in a molecule that is not directly involved in the bond-breaking or bond-forming steps of a reaction. These effects arise from changes in vibrational frequencies, which alter the zero-point energy of reactants and transition states. They provide insights into changes in hybridization and steric effects during a reaction.",
  "subject": "Organic and Biomolecular Chemistry",
  "see_also": [
    "equilibrium constant",
    "hybridization",
    "hyperconjugation",
    "isotope effect",
    "kinetic isotope effect",
    "pre-equilibrium",
    "primary isotope effect",
    "rate-controlling step",
    "steric isotope effect"
  ],
  "references": [
    "PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1131 (https://doi.org/10.1351/pac199466051077)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/secondary-isotope-effect/"
}