The Glass Transition Temperature of Water: A Simulation Study

TL;DR

This simulation study investigates the glass transition temperature of water by analyzing specific heat changes in differently cooled glassy states, providing insights into debated values and comparing with phenomenological models.

Contribution

It introduces a simulation approach to study water's glass transition, highlighting effects of cooling rates and comparing results with existing models.

Findings

Detection of a weak pre-peak in specific heat indicating a shadow transition

Identification of a prominent glass transition peak at higher temperature

Comparison of simulation results with the Tool-Narayanaswamy-Moynihan model

Abstract

We report a computer simulation study of the glass transition for water. To mimic the difference between standard and hyperquenched glass, we generate glassy configurations with different cooling rates and calculate the $T$ dependence of the specific heat on heating. The absence of crystallization phenomena allows us, for properly annealed samples, to detect in the specific heat the simultaneous presence of a weak pre-peak (``shadow transition''), and an intense glass transition peak at higher temperature. We discuss the implications for the currently debated value of the glass transition temperature of water. We also compare our simulation results with the Tool-Narayanaswamy-Moynihan phenomenological model.