Cooperativity and Anticooperativity in Ion‐Water Interactions: Implications for the Aqueous Solvation of Ions

Abstract

Non‐additive effects in hydrogen bonds (HB) take place as a consequence of electronic charge transfers. Therefore, it is natural to expect cooperativity and anticooperativity in ion‐water interactions. Nevertheless, investigations on this matter are scarce. This paper addresses the interactions of (i) the cations Li+, Na+, K+, Be2+, Mg2+, and Ca2+ together with (ii) the anions F−, Cl−, Br−, NO3− and SO42− with water clusters (H2O)n, n=1–8, and the effects of these ions on the HBs within the complete molecular adducts. We used quantum chemical topology tools, specifically the quantum theory of atoms in molecules and the interacting quantum atoms energy partition to investigate non‐additive effects among the interactions studied herein. Our results show a decrease on the interaction energy between ions and the first neighbouring water molecules with an increment of the coordination number. We also found strong cooperative effects in the interplay between HBs and ion‐dipole interactions within the studied systems. Such cooperativity affects considerably the interactions among ions with their first and second solvation shells in aqueous environments. Overall, we believe this article provides valuable information about how ion‐dipole contacts interact with each other and how they relate to other interactions, such as HBs, in the framework of non‐additive effects in aqueous media.

Partition of the electronic energy of the PM7 methodviathe interacting quantum atoms approach

“…8. Indeed, the occurrence of multiple hydrogen bond acceptors has been identified as a source of H-bond anticooperativity 26,50–52…”

Anticooperativity of Multiple Halogen Bonds and Its Effect on Stoichiometry of Cocrystals of Perfluorinated Iodobenzenes

“…One of the most fascinating aspects of the study of intermolecular interactions is the effect one interaction can have on other interactions present in the same structure. − This effect can be manifested through strengthening (cooperativity) or weakening (anticooperativity) of the interactions involved. This has particularly been studied in the case of hydrogen bonds − where (anti)­cooperativity and multiple hydrogen bonds have been found to have a profound effect on the properties of liquids, − hydration of ions, − the structures of biological macromolecules, − etc. Cooperativity of hydrogen bonds is most commonly present in hydrogen bonded chains where the atom which is the donor of one hydrogen bond is an acceptor of another (sequence D–H···D–H···), while anticooperativity is most pronounced in systems with multiple hydrogen bonds involving the same donor or the same acceptor atom (sequences D–H···A···H–D and A···H–D–H···A).…”

A “Two‐in‐One” Strategy for Flexible Aqueous Batteries Operated at −80 °C

“…These interactions impaired the original HBs between the water molecules resulting in reduced water freezing point. [32,33] With the interactions lowering the freezing point of water, the IL-OH, with ion center and hydroxyl substituted groups, can interact with water molecules by both hydrogen bond and ionic hydration interactions leading to improved antifreezing properties. Figure 1B shows the procedure for the synthesis of the PIL-OH hydrogels.…”