On the insights into phases of liquid water from study of its unusual glass-forming properties

TL;DR

This study critically examines the thermodynamic interpretation of water's glass-forming properties, finding no evidence for lambda-type ordering transitions in nanoconfined supercooled water based on heat capacity data analysis.

Contribution

The paper challenges previous interpretations by analyzing heat capacity data, showing that water's properties do not support lambda-transition analogies or cooperative ordering in supercooled states.

Findings

Heat capacity peak was artificially constructed from disparate data.

Only three water molecules fit in the nanoconfined pores studied.

No evidence of lambda-type transition or cooperative motions in supercooled water.

Abstract

We investigate whether an interpretation of water's thermodynamics [Science, 319, 582 (2008)] by using analogy with the binary metal alloys lambda-type ordering transition or buckminsterfullerene's orientational-ordering transition has merit. On examining the heat capacity data used for the nanoconfined water, the construction of the heat capacity peak, and the number of water molecules in nanoconfinement, we find that (i) the peak had been obtained by joining the data for emulsified water with that of the nanoconfined water and (ii) only three water molecules can be fitted across the 1.1 nm diameter pores used in the study, two of which form a cylindrical shell that is hydrogen bonded to silica. The remaining connectedness of one water molecule would not produce a metal alloy-like lambda-transition, or cooperative motions. Therefore, there is no basis for considering such an ordering in supercooled water.