Relationships between interaction energy, intermolecular distance and electron density properties in hydrogen bonded complexes under external electric fields

The hydrogen bond interaction energy ( E HB ) of HF⋯HR (R = H, Li, Al, Cl, CCH) complexes under external electric fields is investigated in terms of the bonding distance and of several properties at the bond critical point. All these properties can be used for the estimation of E HB , being the positive curvature along the hydrogen bond path the most suited for the application to experimental electron densities.