Analysis of values and signs of activation energies of temperature dependences (TDs) for 15 physical characteristics of water, in the temperature range of 0 °C to ~100 °C, has shown that molecular dynamics of water comes from the synergism of endothermic and exothermic transformations of hydrogen bonds in dynamic supramolecular structure (SMS). Application of Arrhenius approximations and modification of TDs made it possible to define their activation energies and to differentiate the contributions of equilibrium thermal processes and those of SMS reconfigurations. Reactions of hydrogen bond breakage and those of hexagonal ice-like cluster transformation limit TDs of viscosity and rotation-translational self-diffusion in the temperature range of 0 °C to ~25 °C. Limitation of degrees of freedom of these motions by the effect of anisotropic external factors leads to the reduction in the activation energy of TDs of compressibility, sound velocity and thermal conductivity by nearly six-fold. Equality of absolute values of activation energies, having opposite signs, for the thermal and configurational components of TD, in its point of extremum, is the condition of TDs’ extrema for volumetric density, heat capacity at constant pressure, compressibility and sound velocity. In this case, space-time correlation of water dynamics takes place, on the SMS level, followed by constant-energy transition between metastable SMS phases.
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