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arXiv · 1901.02772

Topological extension of the isomorph theory based on the Shannon entropy

Abstract

Isomorph theory is one of the promising theories to understand the quasi-universal relationship between thermodynamic, dynamic and structural characteristics. Based on the hidden scale invariance of the inverse power law potentials, it rationalizes the excess entropy scaling law of dynamic properties. This work aims to show that this basic idea of isomorph theory can be extended by examining the microstructural features of the system. Using the topological framework in conjunction with the entropy calculation algorithm, we demonstrate that Voronoi entropy, a measure of the topological diversity of single atoms, provides a scaling law for the transport properties of soft-sphere fluids, which is comparable to the frequently used excess entropy scaling. By examining the relationship between the Voronoi entropy and the solid-like fraction of simple fluids, we suggest that the Frenkel line, a rigid-nonrigid crossover line, {be} a topological isomorphic line where the scaling relation qualitatively changes.

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BibTeXRIS

Tae Jun Yoon, Min Young Ha, Emanuel A. Lazar, Won Bo Lee, Youn-Woo Lee. 2019-07-30. Topological extension of the isomorph theory based on the Shannon entropy. https://doi.org/10.1103/physreve.100.012118

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