Hydrogen bonding : the role of hydrogen delocalization in the AHB bond

The behavior of the A-H...B multiple minimum hydrogen bond can be understood in terms of an analysis similar to the molecular orbital method in molecular electronic quantum theory. Delocalization of hydrogen about two or more wells is described in terms of a linear combination of Gaussian orbitals, each referred to a well minimum. The analysis yields an effective A-B potential mediated by hydrogen. The role of a model three-center interaction in the potential is found to be important and can account for much of the strength of the hydrogen bond