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A semi-schematic model for the center of mass dynamics in supercooled molecular liquids

Linda Fabbian·Francesco Sciortino·Filippo Thiery·Piero Tartaglia
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Abstract

We introduce a semi-schematic mode-coupling model to describe the slow dynamics in molecular liquids, retaining explicitly only the description of the center of mass degrees of freedom. Angular degrees of freedom are condensed in a q-vector independent coupling parameter. We compare the time and q-dependence of the density fluctuation correlators with numerical data from a 250 ns long molecular dynamics simulation. Notwithstanding the choice of a network-forming liquid as a model for comparing theory and simulation, the model describes the main static and dynamic features of the relaxation in a broad q-vector range.

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Linda Fabbian, Francesco Sciortino, Filippo Thiery, Piero Tartaglia. 1997-07-08. A semi-schematic model for the center of mass dynamics in supercooled molecular liquids. https://doi.org/10.1103/physreve.57.1485

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