Dielectric relaxation of water below the melting point: the effect of inner pressure

TL;DR

This study investigates how inner pressure affects the dielectric relaxation of supercooled water below its melting point, revealing phase transitions and relaxation behaviors similar to ice Ih and potentially forming ice III.

Contribution

It provides new dielectric measurements of supercooled water under constrained conditions, showing pressure-induced phase behavior and the formation of ice III at 251 K.

Findings

Inner pressure shifts the α relaxation peak to frequencies similar to ice Ih.

Ice III formation observed at 251 K under constrained conditions.

Dielectric properties reveal phase transitions in supercooled water.

Abstract

Despite water is the most studied substance in the Earth, it is not completely understood why its structural and dynamical properties give rise to some anomalous behaviors. Interesting properties emerge when experiments at low temperatures and/or high pressures, are performed. Here we report dielectric measurements of cold water under constrained conditions, i.e. water that below the melting point can not freeze. The inner pressure shifts the {\alpha} relaxation peak to similar frequencies as seen in ice Ih. Also, when we reach the triple point at 251 K, ice III seems to form. As far as we know, this via to obtain such crystalline phase has not been observed.