Transitional hydrogen bonds in aqueous perchlorate solution

Abstract

Different mechanisms of H-bond formation between perchlorate anions and water are presented using the molecular dynamics simulations. The detailed methods in searching for multi-centered hydrogen bonds are proposed. The time evolution of H-bond geometric parameters for classical, bifurcated and trifurcated hydrogen bonds in the aqueous perchlorate solution indicates the transitional character of hydrogen bridges as well as the rigid nature of the solvation structure formed by the ion and its first solvation shell. This is supported by the values of free energy binding of water to perchlorate ions determined for particular types of hydrogen bridges.

TrimethylamineN-oxide (TMAO) resists the compression of water structure by magnesium perchlorate: terrestrial kosmotropevs.Martian chaotrope

“…This is also the case for the addition of 0.2 M Mg(ClO4)2 to pure water. All three criteria decrease, consistent with previous findings that strong interactions between water molecules and Mg 2+ and ClO4ions cause an increase in hydrogen bond reorientation time (9,17,19,20,22). The ability to calculate distributions of the interaction energies between ions and water molecules was not included in the hydrogen bonding analysis routine.…”

“…Its maximum density at 4 o C, unusually high heat capacity and low compressibility are examples of these. The response of the hydrogen bonded loosely packed network of liquid water to solutes such as ions and amphiphilic molecules has been examined in depth by techniques such as Raman(6,7), IR spectroscopy (8)(9)(10)(11)(12)(13)(14), molecular dynamics simulations (15)(16)(17)(18)(19)(20)(21)(22), NMR(23), X-ray diffraction (24,25) and neutron diffraction (26)(27)(28)(29)(30)(31)(32)(33), which has allowed us to visualise structure making (kosmotropic) and structure breaking (chaotropic) effects. One of the most striking results is the modification to water structure as a result of ion addition, which is often similar to that of pure water under pressure (29,30).…”

Salting-in/Salting-out Mechanism of Carbon Dioxide in Aqueous Electrolyte Solutions

“…[20] and Ref. [21] respectively. In running simulations, the geometries of water and ions were kept rigid by the LINCS Algorithm [22].…”

Co-Poly(ionic liquid) Films via Anion Exchange for the Continuous Tunability of Ion Transport and Wettability

“…25 However, ClO 4 – anions have a negligible impact on the hydrogen bond (H-bond) network in bulk water because of the transitional character of the water–perchlorate H-bond, which mirrors the dynamic, labile H-bond networks observed for liquid water, resulting in a strong interaction between the ClO 4 – anion and water molecules. 26,27 As the PF 6 – anions in solution migrate toward the working electrode because of changes in potential, an exchange of PF 6 – anions from the solution phase to the film phase occurs. As a result of the weak interaction between the PF 6 – anions and water, the thermodynamic equilibrium lies toward the film, and a large ion transport resistance through the p[N 1 -dMIm][PF 6 ] film is observed.…”