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arXiv · 1204.2501

Diffusion coefficient and shear viscosity of rigid water models

Sami Tazi·Alexandru Botan·Mathieu Salanne·Virginie Marry·Pierre Turq·Benjamin Rotenberg
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Abstract

We report the diffusion coefficient and viscosity of popular rigid water models: Two non polarizable ones (SPC/E with 3 sites, and TIP4P/2005 with 4 sites) and a polarizable one (Dang-Chang, 4 sites). We exploit the dependence of the diffusion coefficient on the system size [Yeh and Hummer, J. Phys. Chem. B 108, 15873 (2004)] to obtain the size-independent value. This also provides an estimate of the viscosity of all water models, which we compare to the Green-Kubo result. In all cases, a good agreement is found. The TIP4P/2005 model is in better agreement with the experimental data for both diffusion and viscosity. The SPC/E and Dang-Chang water overestimate the diffusion coefficient and underestimate the viscosity.

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BibTeXRIS

Sami Tazi, Alexandru Botan, Mathieu Salanne, Virginie Marry, Pierre Turq, Benjamin Rotenberg. 2012-04-11. Diffusion coefficient and shear viscosity of rigid water models. https://doi.org/10.1088/0953-8984%2F24%2F28%2F284117

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