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Although it has the geometric characteristics of a halogen bond, the binding between a square planar metal and a halogen atom rests primarily on transfer from the halogen lone pairs to the metal π-hole. 

A H-bond is not possible if the bridging H bears a substantial negative charge. Only a very weak, marginal, H-bond is possible if its charge borders on neutrality. 

Strong negative charge on the tetravalent apical C of propellane can attract an electrophile, which can then extract charge from the prominent lobe of its C–C bonding orbital, to form a strong noncovalent bond with C as an electron donor. 

The occurrence of these anion⋯anion dimers in the crystal structure are dependent on the presence of counterions as the attraction between two Au(iii) centers is insufficient to override the coulombic repulsion. 

Quantum calculations show that replacement of the H-bonds within DNA base pairs by halogen bonds can enhance their binding to one another. 

The ability of IR and NMR spectra to distinguish between hydrogen and halogen bonding of haloforms is assessed by quantum chemical calculations. 

ABSTRACT The interaction energies within noncovalent bonds can be partitioned into electrostatic, induction, and dispersive attractive elements. A set of complexes comprising halogen, chalcogen, pnicogen, and tetrel bonds, are studied by quantum chemical calculations to assess how each of these components can be understood on the basis of properties of the constituent monomers. The variation of the electrostatic term, which accounts for over half of the total attractive energy, can be approximated, but with only modest accuracy, by combination of the maximum and minimum of the electrostatic potential on the two subunits. Induction represents a smaller contribution to the total, but is well connected with the NBO interorbital transfer energy, as opposed to the reciprocal of the HOMO‐LUMO gap which behaves quite differently than IND. Of the various AIM parameters, both the bond critical point density and energy density are closely related to the full interaction energy. 

The configuration of certain molecules facilitates the existence of both a σ and π-hole on the same atom. DFT calculations evaluate which site provides a stronger bond with a nucleophile.