Self-absorption

{
  "id": "MLC-T-CHM-010698",
  "term": "Self-absorption",
  "field": "Chemistry",
  "definition": "The re-absorption of emitted radiation by the same substance that produced it, occurring when the emitted photons excite other atoms or molecules of the substance. This process reduces the observed intensity of the emitted radiation, particularly at the center of spectral lines. It is a common phenomenon in spectroscopy, affecting the accuracy of quantitative measurements.",
  "subject": "Organic and Biomolecular Chemistry",
  "see_also": [
    "radiant energy",
    "radiant intensity"
  ],
  "references": [
    "Orange Book, 2nd ed., p. 242 (https://media.iupac.org/publications/analytical_compendium/)",
    "PAC, 1994, 66, 2513. 'Nomenclature for radioanalytical chemistry (IUPAC Recommendations 1994)' on page 2525 (https://doi.org/10.1351/pac199466122513)",
    "PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2273 (https://doi.org/10.1351/pac199668122223)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/self-absorption/"
}