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Strong to fragile transition in a model of liquid silica

Jean-Louis Barrat·James Badro·Philippe Gillet
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Abstract

The transport properties of an ionic model for liquid silica at high temperatures and pressure are investigated using molecular dynamics simulations. With increasing pressure, a clear change from "strong" to "fragile" behaviour (according to Angell's classification of glass-forming liquids) is observed, albeit only on the small viscosity range that can be explored in MD simulations.. This change is related to structural changes, from an almost perfect four-fold coordination to an imperfect five or six-fold coordination. (submitted to "Molecular Simulation")

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Jean-Louis Barrat, James Badro, Philippe Gillet. 1996-12-17. Strong to fragile transition in a model of liquid silica. https://arxiv.org/abs/cond-mat/9612154

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