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arXiv · 2006.15295

Liquid-liquid-like phase transitions between high, mid, and low density phases in confined water

Saeed Pourasad·Amir Hajibabaei·Chang Woo Myung·Kwang S. Kim
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Abstract

Liquid-liquid phase transition (LLPT) in supercooled water has been a long-standing controversial issue. We show simulation results of real stable first-order phase transitions between high and low density liquid (HDL and LDL)-like structures in confined supercooled water in both positive and negative pressures. These topological phase transitions originate from H-bond network ordering in molecular rotational mode after molecular exchanges are frozen. It is explained by the order parameter-dependent free energy change upon mixing liquid-like and ice-like moieties of H-bond orientations which is governed by their two- to many-body interactions. This unexplored purely H-bond orientation-driven topological phase gives mid-density and stable intermediate mixed-phase with high and low density structures. The phase diagram of supercooled water demonstrate the second and third critical points of water.

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Saeed Pourasad, Amir Hajibabaei, Chang Woo Myung, Kwang S. Kim. 2020-06-27. Liquid-liquid-like phase transitions between high, mid, and low density phases in confined water. https://arxiv.org/abs/2006.15295

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