8th Liquid Matter Conference September 6-10, 2011 Wien, Austria ...

P2.70Tue 611:23-14:00Excess entropy and diffusivity of water in a supercooledaqueous solution of saltMauro Rovere, 1 Dario Corradini, 2 and Paola Gallo 11 Physics Department University of Roma Tre, Via della Vasca Navale 84, I-00146, Roma,Italy2 Physics Department Boston University, Boston, Ud States of AmThe excess entropy of bulk TIP4P water is calculated from the structural information extractedfrom the oxygen-oxygen pair correlation function (PCF). The analogous quantity is calculatedin a NaCl aqueous solution from the linear combination of the oxygen-oxygen and oxygen-saltPCF. The PCF are obtained by performing molecular dynamics simulations in both systems uponsupercooling and approaching the region of the liquid-liquid transition [1,2]. The excess entropyin both cases shows the temperature dependence predicted by the Rosenfeld-Tarazona law [3]. Therelationship between the excess entropy and the diffusion constant is explored along the isochoresand the isotherms. A Rosenfeld scaling law [4,5] for the reduced diffusion coefficient is verifiedin the low temperature regime for bulk water and water in solution [6]. Possible connections withthe anomalies of water are considered [7].[1] D. Corradini, M. Rovere and P. Gallo J. Chem. Phys. 132, 134508 (2010).[2] D. Corradini, M. Rovere and P. Gallo J. Phys. Chem. B 115, 1461 (2011).[3] Y. Rosenfeld and P. Tarazona Mol. Phys. 95, 141 (1998).[4] Y. Rosenfeld Phys. Rev. A 15, 2545 (1977); Phys. Rev. E 62, 7524 (2000).[5] J. Mittal, J. R. Errington and T. M. Truskett J. Phys. Chem. B 110, 18147 (2006).[6] M. Rovere, D. Corradini and P. Gallo, in preparation (2011).[7] Z. Yan, S. V. Buldyrev and H. E. Stanley Phys. Rev. E 78, 051201 (2008).70