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arXiv · 1306.4699

Isomorphs, hidden scale invariance, and quasiuniversality

Jeppe C. Dyre
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Abstract

This paper first establishes an approximate scaling property of the potential-energy function of a classical liquid with good isomorphs (a Roskilde-simple liquid). This "pseudohomogeneous" property makes explicit that - and in which sense - such a system has a hidden scale invariance. The second part gives a potential-energy formulation of the quasiuniversality of monatomic Roskilde-simple liquids, which was recently rationalized in terms of the existence of a quasiuniversal single-parameter family of reduced-coordinate constant-potential-energy hypersurfaces [J. C. Dyre, Phys. Rev. E 87, 022106 (2013)]. The new formulation involves a quasiuniversal reduced-coordinate potential-energy function. A few consequences of this are discussed.

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Jeppe C. Dyre. 2013-10-09. Isomorphs, hidden scale invariance, and quasiuniversality. https://doi.org/10.1103/physreve.88.042139

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