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arXiv · 1107.4441

Polymorphism, thermodynamic anomalies and network formation in an atomistic model with two internal states

Chandana Mondal·Surajit Sengupta
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Abstract

Using molecular dynamics simulations we study the temperature-density phase diagram of a simple model system of particles in two dimensions. In addition to translational degrees of freedom, each particle has two internal states and interacts with a modified Lennard-Jones potential which depends on relative positions as well as the internal states. We find that, despite its simplicity, the model has a rich phase diagram showing many features of common network-forming liquids such as water and silica, including polymorphism and thermodynamic anomalies. We believe our model may be useful for studies concerning generic features of such complex liquids.

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Chandana Mondal, Surajit Sengupta. 2011-07-22. Polymorphism, thermodynamic anomalies and network formation in an atomistic model with two internal states. https://doi.org/10.1103/physreve.84.051503

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