Natural hybrid orbital composition

However, a localized adaptation of the natural orbital algorithm allows one to similarly describe/civ-center molecular subregions in optimal fashion, corresponding to the localized lone pairs (one-center) and bonds (two-center) of the chemist s Lewis structure picture. The Natural Bond Orbitals (NBOs) that emerge from this algorithm are intrinsic to, uniquely determined by, and optimally adapted to localized description of, the system wavefunction. The compositional descriptors of NBOs map directly onto bond hybridization, polarization, and other freshman-level bonding concepts that underlie the modem electronic theory of valency and bonding. 

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