These are preliminary reports that have not been peer-reviewed. They should not be regarded as conclusive, guide clinical practice/health-related behavior, or be reported in news media as established information. For more information, please see our FAQs.

Strong Hydrogen Bonds Are Not Shielded in Ionic Liquids

submitted on 04.06.2019 and posted on 05.06.2019 by Teresa Naranjo, Rubén Álvarez-Asencio, Patricia Pedraz, Belén Nieto-Ortega, Enrique Burzurí, Mark W. Rutland, Emilio Pérez
Hydrogen bonds are arguably the most important of noncovalent interactions. The physical properties of water and the information storage in DNA depend on H-bonding, for instance. To this day, the balance between the Coulombic and covalent contributions to H-bonds is still under debate. Here, we show that H-bonded host-guest systems associate in ionic liquids, pure salts with melting point below room temperature, in which dipole-dipole electrostatic interactions should be negligible in comparison with dipole-charge interactions. Binding constants (Ka) obtained from titrations of four H-bonded host-guest systems in two organic solvents and two ionic liquids yield smaller yet comparable Kavalues in ionic liquids than in organic solvents. We also detect the association event using force spectroscopy. Our results indicate that strong H-bonds are only moderately affected by surroundings composed entirely of charges, suggesting that the balance of Coulombic to covalent forces is not tipped towards the former.


Email Address of Submitting Author


IMDEA Nanociencia



ORCID For Submitting Author


Declaration of Conflict of Interest

No conflict of interest