Edmiston-Ruedenberg localization molecular orbitals

Numerical LMOs of this work are determined by the natural localized-molecular-orbital (NLMO) method A. E. Reed and F. Weinhold, J. Chem. Phys. 83 (1985), 1736. The LMOs determined by other methods (e.g., C. Edmiston and K. Ruedenberg, Rev. Mod. Phys. 34 [1963], 457 and J. M. Foster and S. F. Boys, Rev. Mod. Phys. 32 [1960], 300) are rather similar, and could be taken as equivalent for present purposes. 

Edmiston, C., Ruedenberg, K. (1963). Localized Atomic and Molecular Orbitals. Reviews of Modem Physics, 35, 451-465. 

In the early 1960s, Edmiston and Ruedenberg placed the localization of molecular orbitals on a somewhat more objective foundation by transforming to that basis in which interorbital exchange is a minimum. Lipscomb and coworkers found that when applied to diborane this approach indeed leads to localized three-centre bonds for the B-H-B bridge. Lipscomb recalls how the localization of molecular orbitals... 

---