Colour centres

{
  "id": "MLC-T-CHM-002252",
  "term": "Colour centres",
  "field": "Chemistry",
  "definition": "Lattice defects in ionic crystals that absorb light in the visible region, causing the crystal to appear colored. These defects typically involve an electron trapped at an anion vacancy or a hole trapped at a cation vacancy. F-centers in alkali halides are a well-known type of color center.",
  "subject": "Physical and Biophysical Chemistry",
  "see_also": [
    "deep energy trap",
    "extrinsic absorption",
    "free charge carriers",
    "photocatalytic centre"
  ],
  "references": [
    "PAC, 2011, 83, 931. 'Glossary of terms used in photocatalysis and radiation catalysis (IUPAC Recommendations 2011)' on page 945 (https://doi.org/10.1351/PAC-REC-09-09-36)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/colour-centres/"
}