Water diffusion model at T=(35-45)С

Research thermodynamic characteristics to assess the impact of physiological temperatures on physicochemical properties of water is a very topical and necessary task that opens the question of the dynamics of water molecules and clusters in the human body by changing (increasing) temperatures. In turn, this is reflected in the temperature dependence of the diffusion coefficient of water. The presented research studied the effect of temperature on the structural and dynamic properties of water at physiological temperatures T = (308÷315) K by using the method of molecular dynamics (MD), which was implemented with a software package DL_POLY with a time step 2fs. Based on the fundamental Frenkel model and phonon theory of liquid thermodynamics, a model relating the structural and dynamical properties of the water systems at temperatures T=(280-350)K introduced. These data suggest that changes in temperature in a given interval leads to a change in the dynamic properties of liquid systems studied. Analysis of the temperature and the time dependence of diffusion allowed to build a model representation describing the mechanisms of diffusion of the systems and calculate their characteristic times.Qualitative analysis of the characteristic of the molecules of water, made from the time dependence of the diffusion coefficient indicates the existence of various mechanisms of diffusion in the studied systems. This is confirmed by a deviation from linear dependence D (T) in physiological T = temperature (308 - 315) K and reduction coefficient diffusion coefficient in this area. To confirm the theoretical predictions, a qualitative comparison of the model with the existing experimental data on temperature influence on the physics properties of water is performed.