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arXiv · 1112.4001

Scaling of Volumetric Data in Model Systems Based on the Lennard-Jones Potential

Andrzej Grzybowski·Kajetan Koperwas·Marian Paluch
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Abstract

The crucial problem for better understanding the nature of glass transition and related relaxation phenomena is to find proper interrelations between molecular dynamics and thermodynamics of viscous systems. To gain this aim the recently observed density scaling of viscous liquid dynamics has been very intensively and successfully studied for last years. However, previous attempts at related scaling of volumetric data yielded results inconsistent with those found from the density scaling of molecular dynamics. In this Letter, we show that volumetric data obtained from simulations in simple molecular models based on the Lennard-Jones (LJ) potential, such as Kob-Andersen binary liquids and the Lewis-Wahnström o-terphenyl model, can be scaled by using the same value of the exponent, which scales dynamic quantities and is directly related to the exponent of the repulsive inverse power law that underlies short-range approximations of the LJ potential.

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Andrzej Grzybowski, Kajetan Koperwas, Marian Paluch. 2011-12-17. Scaling of Volumetric Data in Model Systems Based on the Lennard-Jones Potential. https://doi.org/10.1103/physreve.86.031501

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