Coordinatively unsaturated complex

{
  "id": "MLC-T-CHM-002566",
  "term": "Coordinatively unsaturated complex",
  "field": "Chemistry",
  "definition": "A complex in which the central metal atom or ion has fewer ligands than its maximum possible coordination number, leaving vacant coordination sites. This condition means the metal center possesses available orbitals of appropriate energy and symmetry to accept additional electron pairs. These complexes are reactive and readily undergo ligand addition or substitution reactions, playing a role in catalysis.",
  "subject": "Organic and Biomolecular Chemistry",
  "see_also": [
    "coordinatively saturated complex",
    "ligands"
  ],
  "references": [
    "PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1100 (https://doi.org/10.1351/pac199466051077)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/coordinatively-unsaturated-complex/"
}