Frontier orbitals

{
  "id": "MLC-T-CHM-004682",
  "term": "Frontier orbitals",
  "field": "Chemistry",
  "definition": "The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of a molecular entity. These orbitals are at the outer edges of the molecule's electron cloud and are the principal participants in chemical bonding and reactivity. The energy difference between the HOMO and LUMO, known as the HOMO-LUMO gap, is a measure of a molecule's excitability and its chemical hardness or softness.",
  "subject": "Organic and Biomolecular Chemistry",
  "see_also": [
    "SOMO",
    "molecular entity",
    "molecular orbital",
    "subjacent orbital"
  ],
  "references": [
    "PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1116 (https://doi.org/10.1351/pac199466051077)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/frontier-orbitals/"
}