https://doi.org/10.1351/goldbook.LT07066
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 @[email protected] 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 @[email protected]) repulsion integrals between the occupied MOs (the Edmiston–Ruedenberg procedure).