Phase diagram and water-like anomalies in core-softened shoulder-dumbbells system

Cristina Gavazzoni; Guilherme K. Gonzatti; Luiz Felipe Pereira; Luis Henrique Coelho Ramos; Paulo A. Netz; Marcia C. Barbosa

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arXiv · 1309.0843

Phase diagram and water-like anomalies in core-softened shoulder-dumbbells system

Cristina Gavazzoni·Guilherme K. Gonzatti·Luiz Felipe Pereira·Luis Henrique Coelho Ramos·Paulo A. Netz·Marcia C. Barbosa

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Abstract

Using molecular dynamics we studied the role of the anisotropy on the phase boundary and on the anomalous behavior of 250 dimeric particles interacting by a core-softened potential. This study led us to an unexpected result: the introduction of a rather small anisotropy, quantified by the distance between the particles inside each dimer, leads to the increase of the size of the regions in the pressure-temperature phase diagram of anomalies when compared to the isotropic monomeric case. However, as the anisotropy increases beyond a threshold the anomalous regions shrinks. We found that this behavior can be understood by decoupling the translational and non-translational kinetic energy components into different translational and non-translational temperatures.

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Cristina Gavazzoni, Guilherme K. Gonzatti, Luiz Felipe Pereira, Luis Henrique Coelho Ramos, Paulo A. Netz, Marcia C. Barbosa. 2013-09-03. Phase diagram and water-like anomalies in core-softened shoulder-dumbbells system. https://arxiv.org/abs/1309.0843

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