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arXiv · 1311.0976

Predicting how nanoconfinement changes the relaxation time of a supercooled liquid

Trond S. Ingebrigtsen·Jeffrey R. Errington·Thomas M. Truskett·Jeppe C. Dyre
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Abstract

The properties of nanoconfined fluids can be strikingly different from those of bulk liquids. A basic unanswered question is whether the equilibrium and dynamic consequences of confinement are related to each other in a simple way. We study this question by simulation of a liquid comprising asymmetric dumbbell-shaped molecules, which can be deeply supercooled without crystallizing. We find that the dimensionless structural relaxation times - spanning six decades as a function of temperature, density, and degree of confinement - collapse when plotted versus excess entropy. The data also collapse when plotted versus excess isochoric heat capacity, a behaviour that follows from the existence of isomorphs in the bulk and confined states.

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Trond S. Ingebrigtsen, Jeffrey R. Errington, Thomas M. Truskett, Jeppe C. Dyre. 2013-11-05. Predicting how nanoconfinement changes the relaxation time of a supercooled liquid. https://doi.org/10.1103/physrevlett.111.235901

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