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arXiv · 0902.2352

Three-dimensional "Mercedes-Benz" model for water

Cristiano L. Dias·Tapio Ala-Nissila·Martin Grant·Mikko Karttunen
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Abstract

In this paper we introduce a three-dimensional version of the Mercedes-Benz model to describe water molecules. In this model van der Waals interactions and hydrogen bonds are given explicitly through a Lennard-Jones potential and a Gaussian orientation-dependent terms, respectively. At low temperature the model freezes forming Ice-I and it reproduces the main peaks of the experimental radial distribution function of water. In addition to these structural properties, the model also captures the thermodynamical anomalies of water: the anomalous density profile, the negative thermal expansivity, the large heat capacity and the minimum in the isothermal compressibility.

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Cristiano L. Dias, Tapio Ala-Nissila, Martin Grant, Mikko Karttunen. 2009-02-13. Three-dimensional "Mercedes-Benz" model for water. https://doi.org/10.1063/1.3183935

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