Buckingham-Fowler model

An electrostatic model for the hydrogen bond interaction the Buckingham-Fowler model... 

In the Buckingham-Fowler model, each monomer electric charge distribution is described by a set of point multipoles (charges, dipoles and quadru-poles) located on the atoms and, sometimes, additionally at bond midpoints. The values of the point multipoles are determined by the so-called distributed multipole analysis (DMA) of an ab initio wavefunction. This multicentric representation of the charge distribution shows superior convergence behaviour to the one-centre molecular multipoles when calculating the electrostatic potential around a molecule. 

The Vsr part accounts for the monomers shape factor in the potential. It mainly includes the exchange effects. However, other effects, such as the overlap-dependent electrostatic interaction, may also be conveniently absorbed in Vsr. Following Buckingham, Fowler and Hutson [14], Vsr may be adequately modeled by a Bom-Mayer exponential form ... 

Figure2.4 Angular geometries predicted for the dimers HjO-.-HF, HjCO-.-HF, HjS---HF and ethene-- - HF by the Buckingham-Fowler electrostatic model.

This approach forms the basis of the Buckingham-Fowler method [12] discussed above. An alternative model [16], which is set out here, begins with the point charges on the atoms but accounts for the deviations from sphericity about atom centres by translating small fractions of the point charges from the acceptor atom centre of B along directions conventionally associated with non-bonding pairs. 

Fowler P W and A D Buckingham 1991. Central or Distributed Multipole Moments Electrostatic Models of Aromatic Dimers. Chemical Physics Letters 176 11-18. 

Baker, J., Buckingham, A. D., Fowler, P. W., Steiner, E., Lazzeretti, R, Zanasi, R. (1989). The electrostatic model of field gradients at nuclei -an application to hydrogen-bonded complexes of... 

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