The role of the H-bond network in the creation of the life-giving properties of water

Abstract

This work is devoted to the study of the properties of water in the physiological temperature range for warm-blooded organisms. Special attention is paid to the nature of thermal motion in bulk water. Through the analysis of data from incoherent neutron scattering in water, it is shown that the crystal-like thermal motion in water takes place only in its supercooled and normal states, the temperature of which does not exceed T H = (310 ± 5) K. A quite similar temperature, T ν = (308 ± 5) K, is also characteristic of the temperature dependence of the kinematic shear viscosity of water. It is shown that the average number of H-bonds per molecule near T H is about 2.1–2.3 because the spatially ordered H-bond network in bulk water becomes unstable. The interpretation of T H as the temperature of the dynamic phase transition from the crystal-like to argon-like character of thermal motion is discussed in detail. It is assumed that the nature of thermal motion in the “cellular water solution” changes analogously at temperatures close to T H. As a result, the problem of protein and DNA denaturation and the death of living organisms is connected with the dynamic phase transition in intracellular water.