Proton ordering dynamics of H2O ice

TL;DR

This study investigates the proton ordering phase transitions in H2O and D2O ice using dielectric measurements, identifying critical temperatures, a triple point, and a first-order transition related to proton dynamics.

Contribution

The paper provides precise critical temperatures for phase transitions in ice Ih and XI, and identifies a triple point and kinetic broadening effects in proton ordering.

Findings

Critical temperatures for ice Ih to XI transition in H2O and D2O.

Existence of a triple point where ices Ih, II, and XI coexist.

First order phase transition with kinetic broadening at 100 K.

Abstract

From high precision measurements of the complex dielectric constant of H2O ice, we identify the critical temperatures of the phase transition into and out of ice XI from ice Ih to occur at T_Ih-IX=58.9 K and T_IX-Ih=73.4 K. For D2O, T_Ih-IX=63.7 K and T_IX-Ih=78.2 K. A triple point is identified to exist at 0.07 GPa and 73.4 K for H2O and 0.08 GPa and 78.2 K for D2O where ices Ih, II and XI coexist. A first order phase transition with kinetic broadening associated to proton ordering dynamics is identified at 100 K.