A test for the existence of isomorphs in glass-forming materials

Abstract

We describe a method to determine whether a material has isomorphs in its thermodynamic phase diagram. Isomorphs are state points for which various properties are invariant in reduced units. Such materials are commonly identified from strong correlation between thermal fluctuations of the potential energy, U, and the virial W, but this identification is not generally applicable to real materials. We show from molecular dynamic simulations of atomic, molecular, and polymeric materials that systems with strong U-W correlation cannot be pressure densified; that is, the density obtained on cooling to the glassy state and releasing the pressure is independent of the pressure applied during cooling.

arXiv comment9 pages, 3 figures

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Cited by in corpus (4)

• Virial-potential energy correlation and its relation to the density scaling for quasi-real model systems
• Effect of density on the physical aging of pressure-densified polymethylmethacrylate
• Scaling properties of liquid dynamics predicted from a single configuration: Small rigid molecules
• Scaling Properties of Liquid Dynamics Predicted from a Single Configuration: Pseudoisomorphs for Harmonic-Bonded Molecules