English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Supercooled water exhibits remarkably slow dynamics similar to the behaviorobserved for various glass-forming liquids. The local order of tetrahedralstructures due to hydrogen-bonds (H-bonds) increases with decreasingtemperature. Thus, it is important to clarify the temperature dependence of theH-bond breakage process. This was investigated here using molecular dynamicssimulations of TIP4P supercooled water. The two-dimensional (2D) potential ofmean force (PMF) is presented using combinations of intermolecular distance andangle between two water molecules. The saddle point of the 2D PMF suggests thepresence of the transition state that distinguishes between H-bond and nonH-bond states. However, we observed pathways not going through this saddlepoint particularly at supercooled states, which are due to translational,rather than rotational motions of the molecules. We quantified thecharacteristic time scales of rotational and translational H-bond breakages.The time scale of translational H-bond breakage shows a non-Arrheniustemperature dependence comparable to that of the H-bond lifetime. This timescale is relevant for the temperature dependence of the transmissioncoefficient based on the transition state theory. The translational H-bondbreakage is also related to cage-jumps observed in glass-forming liquids, whichmostly involve spatially correlated molecules. Our findings warrant furtherexploration of an appropriate free-energy surface or reaction coordinatesbeyond the geometrical variables of the water dimer to describe a possiblesaddle point related to collective jump motions.

How do hydrogen bonds break in supercooled water?: Detecting pathways not going through the saddle point of two-dimensional potential of mean force