Digital Object Identifier (DOI)
The Attenuated Total Reflection – Fourier Transform Infrared (ATR-FTIR) spectra of the OH-stretch band in aqueous solutions of inorganic salts and organic materials; Na2SO4, NaCl, NaClO4, NaSCN, trimethylamine N-oxide, urea, poly(ethylene glycol), polyvinylpyrrolidone, and copolymer of ethylene glycol and propylene glycol (Ucon) were studied at various concentrations. The decomposition of the band into four Gaussian components peaking at 3080, 3230, 3400, and 3550 cm−1 fits every compound examined here with essentially flat residuals. These components were viewed as representing four different subpopulations of water with different H-bond arrangements. The experimentally estimated relative contributions of these components depend on solute type and concentration, and correlate strongly with previously reported experimentally measured solvent features of water such as solvent dipolarity/polarizability, π*, solvent H-bond donor acidity, α, and solvent H-bond acceptor basicity, β. We suggest that water includes an ensemble of four different subpopulations of molecules with various hydrogen bond strengths, geometry, and bond defects depending on the solute. This assumption is obviously oversimplified, but for the wide range of solutes examined here we find that a given solute changes the relative amounts of these subpopulations and hence the above solvent features of water. The solvent features, π* and α, in particular, describe a variety of physicochemical properties, such as water activity, osmotic coefficient, relative viscosity, permittivity, and surface tension, of aqueous solutions of various compounds. It follows therefore that all these physicochemical properties of aqueous solutions are determined by the relative amounts of the above subpopulations of water molecules.
Was this content written or created while at USF?
Citation / Publisher Attribution
Journal of Molecular Liquids, v. 335, art. 116288
This article is the post-print author version. Final version available at: https://doi.org/10.1016/j.molliq.2021.116288
Scholar Commons Citation
da Silva, Nuno; Ferreira, Luisa A.; Belgovskiy, Alexander I.; Madeira, Pedro P.; Teixeira, José A.; Mann, Elizabeth K.; Adin Mann, J.; Meyer, William V.; Smart, Anthony E.; Chernyak, Vladimir Y.; Uversky, Vladimir N.; and Zaslavsky, Boris Y., "Effects of Different Solutes on the Physical Chemical Properties of Aqueous Solutions via Rearrangement of Hydrogen Bonds in Water" (2021). Molecular Medicine Faculty Publications. 172.