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arXiv · 1802.02810

Potential Energy Landscape of TIP4P/2005 water

Philip H. Handle·Francesco Sciortino
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Abstract

We report an exhaustive numerical study of the statistical properties of the potential energy landscape of TIP4P/2005, one of the most accurate rigid water models. We show that, in the region where equilibrated configurations can be generated, a Gaussian landscape description is able to properly describe the model properties. We also find that the volume dependence of the landscape properties is consistent with the existence of a locus of density maxima in the phase diagram. The landscape-based equation of state accurately reproduces the TIP4P/2005 pressure-vs-volume curves, providing a sound extrapolation of the free-energy at low T. A positive-pressure liquid-liquid critical point is predicted by the resulting free-energy.

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Philip H. Handle, Francesco Sciortino. 2018-02-08. Potential Energy Landscape of TIP4P/2005 water. https://doi.org/10.1063/1.5023894

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