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arXiv · 1912.08176

Density scaling of generalized Lennard-Jones fluids in different dimensions

Thibaud Maimbourg·Jeppe C. Dyre·Lorenzo Costigliola
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Abstract

Liquids displaying strong virial-potential energy correlations conform to an approximate density scaling of their structural and dynamical observables. This scaling property does not extend to the entire phase diagram, in general. The validity of the scaling can be quantified by a correlation coefficient. In this work a simple scheme to predict the correlation coefficient and the density-scaling exponent is presented. Although this scheme is exact only in the dilute gas regime or in high dimension d, a comparison with results from molecular dynamics simulations in d = 1 to 4 shows that it reproduces well the behavior of generalized Lennard-Jones systems in a large portion of the fluid phase.

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Thibaud Maimbourg, Jeppe C. Dyre, Lorenzo Costigliola. 2019-12-17. Density scaling of generalized Lennard-Jones fluids in different dimensions. https://doi.org/10.21468/scipostphys.9.6.090

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