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PubMed · 15664897

Simulated silica.

Ivan Saika-Voivod·Francesco Sciortino·Tor Grande·Peter H Poole
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Abstract

We review how molecular dynamics computer simulations are providing a comprehensive picture of the behaviour of silica, as modelled by the van Beest-Kramer-van Santen (BKS) potential. We have recently evaluated a number of key properties of this model system: the phase diagram, including melting lines of three crystal phases; the equation of state and free energy of the liquid phase; the dynamical equation of state; the average energy of inherent structures, and configurational entropy, associated with the potential energy landscape of the liquid; and a characterization of the local coordination environments in the supercooled liquid. The results reveal the interplay among a number of phenomena, in particular, the relationship between the energy landscape and the fragile-to-strong crossover of the liquid dynamics; and the relation of both of these to the possibility of a liquid-liquid phase transition in the supercooled liquid.

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Computer SimulationCrystallographyEnergy TransferMacromolecular SubstancesModels, ChemicalModels, MolecularMolecular ConformationPhase TransitionSilicon DioxideSolutionsTemperatureJournal ArticleResearch Support, Non-U.S. Gov'tReview

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Ivan Saika-Voivod, Francesco Sciortino, Tor Grande, Peter H Poole. 2005-02-15. Simulated silica.. https://doi.org/10.1098/rsta.2004.1506

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