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arXiv · 0812.4922

Waterlike thermodynamic anomalies in a repulsive-step potential system

N. V. Gribova·Yu. D. Fomin·Daan Frenkel·V. N. Ryzhov
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Abstract

We report a computer-simulation study of the equilibrium phase diagram of a three-dimensional system of particles with a repulsive step potential. The phase diagram is obtained using free-energy calculations. At low temperatures, we observe a number of distinct crystal phases. We show that at certain values of the potential parameters the system exhibits the water-like thermodynamic anomalies: density anomaly and diffusion anomaly. The anomalies disappear with increasing the repulsive step width: their locations move to the region inside the crystalline phase.

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N. V. Gribova, Yu. D. Fomin, Daan Frenkel, V. N. Ryzhov. 2008-12-29. Waterlike thermodynamic anomalies in a repulsive-step potential system. https://doi.org/10.1103/physreve.79.051202

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