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arXiv · 1206.1572

Multiple liquid-liquid critical points and anomalies in core-softened potentials

Marco Aurélio A. Barbosa·Evy Salcedo·Marcia Barbosa
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Abstract

The relation between liquid-liquid phase transitions and waterlike density anomalies in core-softened potentials of fluids was investigated in an exactly solvable one dimensional lattice model and a in a three dimensional fluid with fermi-like potential, the latter by molecular dynamics. Both systems were shown to present three liquid phases, two liquid-liquid phase transitions closely connected to two distinct regions of anomalous density increase. We propose that an oscillatory behavior observed on the thermal expansion coefficient as a function of pressure can be used as a signature of the connection between liquid-liquid phase and density.

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Marco Aurélio A. Barbosa, Evy Salcedo, Marcia Barbosa. 2012-06-19. Multiple liquid-liquid critical points and anomalies in core-softened potentials. https://doi.org/10.1103/physreve.87.032303

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