The importance of cooperativity for the properties of liquid water

Abstract

The cooperativity of H-bonds is a fundamental property in liquid water and alcohols. H-bond energies are in liquid water about 250% stronger compared with H-bonds of H 2O monomers in solutions. Different spectroscopic techniques fundamental bands, overtone bands, so-called simultaneous bands of neighbouring H-bonded OH groups by one quantum, cooperativity spectroscopy comparison between alcohol and water spectra, solution spectra and discussion of IR intensities could together give a unique model of such liquids. The strong influence of cooperativity on properties of liquid water and alcohols dominates under saturation conditions until about 230 °C. The anomalous water adsorption on surfaces is one example of the importance of cooperativity on properties of water. The anomalous viscosity of water-alcohol mixtures demonstrates the importance of non-H-bonded OH groups in liquid water. The IR overtone spectra show these groups but the fundamental is more difficult. We approximate the complex large clusters below 130 °C as described by a simple equilibrium of cooperative H-bonded and non-bonded OH groups. Equilibrium constants and H-bond energies are estimated. The coupling with weak cooperative H-bonds near the cluster surfaces are discussed.