Effect of total and pair configurational entropy in determining dynamics of supercooled liquids over a range of densities

Abstract

In this paper, we present a study of supercooled liquids interacting with the Lennard Jones (LJ) potential and the corresponding purely repulsive (Weeks-Chandler-Andersen or WCA) potential, over a range of densities and temperatures, in order to understand the origin of their different dynamics in spite of their structures being similar. Using the configurational entropy as the thermodynamic marker via the Adam Gibbs (AG) relation, we show that the difference in the dynamics of these two systems at low temperatures can be explained from thermodynamics. At higher densities both the thermodynamical and dynamical difference between these model systems decrease, which is quantitatively demonstrated in this paper by calculating different parameters. The study also reveals the origin of the difference in pair entropy despite the similarity in the structure. Although the maximum difference in structure is obtained in the partial radial distribution function (rdf) of the B type of particles, the rdf of AA pairs and AB pairs give rise to the differences in the entropy and dynamics. This work supports the observation made in an earlier study (Phys. Rev. Lett.,\textbf {113}, 225701, 2014) and shows that they are generic in nature, independent of density.

12 pages,11 figures

References in corpus (12)

• Growing length and time scales in glass forming liquids
• Identification of long-lived clusters and their link to slow dynamics in a model glass former
• A repulsive reference potential reproducing the dynamics of a liquid with attractions
• Locally preferred structures and many-body static correlations in viscous liquids
• The role of attractive forces in viscous liquids
• A critical test of the mode-coupling theory of the glass transition
• Multiple length and time scales of dynamic heterogeneities in model glass-forming liquids: A systematic analysis of multi-point and multi-time correlations
• The role of structure and entropy in determining differences in dynamics for glass formers with different interaction potentials
• Dependence of the fragility of a glass former on the softness of interparticle interactions
• Static triplet correlations in glass-forming liquids: A molecular dynamics study
• Unraveling the success and failure of mode coupling theory from consideration of entropy
• Do the repulsive and attractive pair forces play separate roles for the physics of liquids?

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