Enthalpy-entropy compensation in biomolecular halogen bonds measured in DNA junctions.

Interest in noncovalent interactions involving halogens, particularly halogen bonds (X-bonds), has grown dramatically in the past decade, propelled by the use of X-bonding in molecular engineering and drug design. However, it is clear that a complete analysis of the structure-energy relationship must be established in biological systems to fully exploit X-bonds for biomolecular engineering. We present here the first comprehensive experimental study to correlate geometries with their stabilizing potentials for fluorine (F), chlorine (Cl), bromine (Br), or iodine (I) X-bonds in a biological context.