Pressure evolution of microscopic diffusion in liquid water

Article type: Research Article

Authors: Cunsolo, A.^; | Orecchini, A.^; | Petrillo, C.^; | Sacchetti, F.^;

Affiliations: CNR-INFM Operative Group in Grenoble, 6 rue J. Horowitz, F-38042 Grenoble Cedex 9, France | Dipartimento di Fisica, Università di Perugia, via A. Pascoli, I-06123 Perugia, Italy | CNR-INFM CRS-SOFT, c/o Università di Roma “La Sapienza”, I-00185 Roma, Italy

Note: [] Corresponding author. Tel.: + 33-476207350. Fax: + 33-476207688. Email: [email protected]

Abstract: The single particle dynamics of liquid water has been investigated as a function of pressure and momentum transfer by quasielastic neutron scattering. A line-shape analysis of the experimental spectra enabled us to extract the values of the microscopic diffusion coefficients. As a result, we observe that the pressure evolution of the translational diffusion coefficient exhibits a neat maximum in its pressure dependence. Moreover, we have also found a monotonic increase of the rotational diffusion coefficient with pressure. Both these effects are clearly reminiscent of the well-known anomalous pressure-behaviour of the macroscopic transport parameters of liquid water.

Keywords: Neutron scattering, Quasielastic neutron scattering, Water, Macroscopic transport parameters

DOI: 10.1080/10238160601049161

Journal: Journal of Neutron Research, vol. 14, no. 4, pp. 309-315, 2006