Term: localized molecular orbitals (LMO)
https://doi.org/10.1351/goldbook.LT07066

Definition:
The molecular orbitals located on certain fragments of a molecular system and spatially separated from each other as much as possible. The LMOs are derived from the electron occupied canonical molecular orbitals by subjecting them to a unitary transformation determined by an appropriate physical criterion, e.g. by maximizing the sum of squares of the centroids of occupied MOs (the Foster–Boys procedure) or by minimizing the sum of the exchange (or Coulomb) repulsion integrals between the occupied MOs (the Edmiston–Ruedenberg procedure).

Related Terms:
1) transformation (http://doi.org/10.1351/goldbook.T06446).
2) coulomb (http://doi.org/10.1351/goldbook.C01365).

Source: PAC, 1999, 71, 1919. 'Glossary of terms used in theoretical organic chemistry' on page 1950 (https://doi.org/10.1351/pac199971101919)

Citation: 'localized molecular orbitals (LMO)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.LT07066

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