Origin of the emergent fragile-to-strong transition in supercooled water

Rui Shi, John Russo, Hajime Tanaka*

*Corresponding author for this work

Research output: Contribution to journalArticle (Academic Journal)peer-review

48 Citations (Scopus)
295 Downloads (Pure)

Abstract

Liquids can be broadly classified into two categories, fragile and strong ones, depending on how their dynamical properties change with temperature. The dynamics of a strong liquid obey the Arrhenius law, whereas the fragile one displays a super-Arrhenius law, with a much steeper slowing down upon cooling. Recently, however, it was discovered that many materials such as water, oxides, and metals do not obey this simple classification, apparently exhibiting a fragile-to-strong transition far above Tg. Such a transition is particularly well known for water, and it is now regarded as one of water’s most important anomalies. This phenomenon has been attributed to either an unusual glass transition behavior or the crossing of a Widom line emanating from a liquid–liquid critical point. Here by computer simulations of two popular water models and through analyses of experimental data, we show that the emergent fragile-to-strong transition is actually a crossover between two Arrhenius regimes with different activation energies, which can be naturally explained by a two-state description of the dynamics. Our finding provides insight into the fragile-to-strong transition observed in a wide class of materials.

Original languageEnglish
Pages (from-to)9444-9449
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume115
Issue number38
Early online date4 Sep 2018
DOIs
Publication statusPublished - 18 Sep 2018

Keywords

  • Dynamic heterogeneity
  • Fragile-to-strong transition
  • Structural origin
  • Two-state model
  • Water’s anomalies

Fingerprint Dive into the research topics of 'Origin of the emergent fragile-to-strong transition in supercooled water'. Together they form a unique fingerprint.

Cite this