Stokes shift

{
  "id": "MLC-T-CHM-011440",
  "term": "Stokes shift",
  "field": "Chemistry",
  "definition": "The difference in wavelength or frequency between the maximum of the absorption spectrum and the maximum of the emission spectrum for a given molecular species. This shift occurs because some energy is lost to vibrational relaxation in the excited state before emission. It is typically observed in fluorescence and phosphorescence phenomena.",
  "subject": "Organic and Biomolecular Chemistry",
  "see_also": [
    "coherent radiation",
    "luminescence",
    "wavelength"
  ],
  "references": [
    "PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2278 (https://doi.org/10.1351/pac199668122223)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/stokes-shift/"
}