Spinodal of supercooled polarizable water

TL;DR

This study uses molecular dynamics simulations with a polarizable water model to investigate the spinodal line and density maximum in supercooled water, supporting the hypothesis of a second critical point.

Contribution

It provides new insights into the behavior of supercooled polarizable water and extends previous non-polarizable models by analyzing the spinodal and density maximum curves.

Findings

Spinodal line decreases monotonically down to 210 K.

Density maximum curve bends near the spinodal line.

Results support the existence of a second critical point for water.

Abstract

We develop a series of molecular dynamics computer simulations of liquid water, performed with a polarizable potential model, to calculate the spinodal line and the curve of maximum density inside the metastable supercooled region. After analysing the structural properties,the liquid spinodal line is followed down to T=210 K. A monotonic decrease is found in the explored region. The curve of maximum density bends on approaching the spinodal line. These results, in agreement with similar studies on non polarizable models of water, are consistent with the existence of a second critical point for water.