Journal Article
Proceedings of the National Academy of Sciences, vol. 118, iss. 14, 2021
Authors
Loni Kringle, Wyatt A. Thornley, Bruce D. Kay, Greg A. Kimmel
Abstract
Significance
Water plays a prominent role in many areas of physical and biological sciences. Water, though commonplace, is also highly unusual in comparison to most liquids. Promising models to explain water’s anomalous properties propose that it is a heterogeneous, temperature-dependent mixture of two structural motifs. Key phenomena related to this structural heterogeneity are predicted to occur for deeply supercooled water where fast crystallization has prevented experiments. We use a pulsed laser heating technique to examine the rate of structural relaxation for supercooled water at previously inaccessible temperatures. The results suggest that the complex relaxation kinetics are governed by a distribution of energetic barriers for rearrangement within a structurally heterogeneous environment. Furthermore, the structural relaxation is always fast compared to crystallization.
