Physical Nature of Hydrogen Bond

Abstract

PHYSICAL NATURE OF HYDROGEN BOND PACS 82.30.RsThe physical nature and the correct definition of hydrogen bond (H-bond) are considered. The influence of H-bonds on the thermodynamic, kinetic, and spectroscopic properties of water is analyzed. The conventional model of H-bonds as sharply directed and saturated bridges between water molecules is incompatible with the behavior of the specific volume, evaporation heat, and self-diffusion and kinematic shear viscosity coefficients of water. On the other hand, it is shown that the variation of the dipole moment of a water molecule and the frequency shift of valence vibrations of a hydroxyl group can be totally explained in the framework of the electrostatic model of H-bond. At the same time, the temperature dependences of the heat capacity of water in the liquid and vapor states clearly testify to the existence of weak H-bonds. The analysis of a water dimer shows that the contribution of weak H-bonds to its ground state energy is approximately 4-5 times lower in comparison with the energy of electrostatic interaction between water molecules. A conclusion is made that H-bonds have the same nature in all other cases where they occur.K e y w o r d s: hydrogen valence vibrations of a water molecule, frequency shift, hydrogen bond, electrostatic origin.The hydrogen bond is a phlogiston of the 20-th century. L. BULAVIN

Вплив температури та тиску на термодинамічний коефіцієнт (∂V/∂T)p води

“…5 and 6 showed that the surfaces of the pressure-temperature dependences of the derivative (𝜕𝑉 /𝜕𝑇 ) 𝑃 for water and argon are qualitatively similar in the intervals of relative temperatures 0.56 < 𝑇 /𝑇 𝑐 < 0.7 and pressures 0.02 < 𝑃/𝑃 𝑐 < 20. This fact confirms the validity of the principle of corresponding states for water and argon and is consistent with the conclusions of works [38][39][40].…”

“…The pressure-temperature dependences of the derivative (𝜕𝑉 /𝜕𝑇 ) 𝑃 for water and argon were analyzed with regard for the principle of corresponding states [26]. Note that, according to works [38][39][40], despite a substantial difference between the properties of water and argon, there exists a temperature interval, at 𝑇 ≪ 𝑇 𝑐 , where the principle of corresponding states can be applied.…”

Вплив температури та хімічного потенціалу на термодинамічний коефіцієнт −(dV/dP)T води

“…5 and 6, the plotted surfaces are qualitatively similar. This fact confirms the validity of the principle of corresponding states in the indicated temperature and chemical potential inter-vals for water and argon, and is in agreement with the conclusions of works [25,[28][29][30].…”

“…To verify the applicability of the principle of corresponding states [26,27], we performed a comparative analysis of the (𝑇, 𝜇)-dependences of the derivative − (𝜕𝑉 /𝜕𝑃 ) 𝑇 for water and argon. It should be noted that, despite a significant difference between the properties of water and argon, nevertheless, according to [28][29][30], there exists a region at 𝑇 < 𝑇 𝑐 (𝑇 𝑐 is the critical temperature), where the principle of corresponding states is applicable. A similar conclusion about the existence of the region of thermodynamic similarity was made in work [25] when analyzing the (𝑇, 𝑝)-dependences of the thermodynamic coefficient (𝜕𝑉 /𝜕𝑇 ) 𝑃 .…”