Viscosity and Stokes-Einstein relation in deeply supercooled water under pressure.

Autor:	Mussa A; Institut Lumière Matière, Université de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Universitaire de France, F-69622 Villeurbanne, France., Berthelard R; Institut Lumière Matière, Université de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Universitaire de France, F-69622 Villeurbanne, France., Caupin F; Institut Lumière Matière, Université de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Universitaire de France, F-69622 Villeurbanne, France., Issenmann B; Institut Lumière Matière, Université de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Universitaire de France, F-69622 Villeurbanne, France.
Jazyk:	angličtina
Zdroj:	The Journal of chemical physics [J Chem Phys] 2023 Oct 21; Vol. 159 (15).
DOI:	10.1063/5.0169743
Abstrakt:	We report measurements of the shear viscosity η in water up to 150 MPa and down to 229.5 K. This corresponds to more than 30 K supercooling below the melting line. The temperature dependence is non-Arrhenius at all pressures, but its functional form at 0.1 MPa is qualitatively different from that at all pressures above 20 MPa. The pressure dependence is non-monotonic, with a pressure-induced decrease of viscosity by more than 50% at low temperature. Combining our data with literature data on the self-diffusion coefficient Ds of water, we check the Stokes-Einstein relation which, based on hydrodynamics, predicts constancy of Dsη/T, where T is the temperature. The observed temperature and pressure dependence of Dsη/T is analogous to that obtained in simulations of a realistic water model. This analogy suggests that our data are compatible with the existence of a liquid-liquid critical point at positive pressure in water. (© 2023 Author(s). Published under an exclusive license by AIP Publishing.)
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu