An interesting twist on supercooled liquid water

February 24, 2016
An interesting twist on supercooled liquid water
Figure: Right- and left-twisted molecular ordering in supercooled liquid water.

Water is known to have various anomalous properties, and they are especially prominent below room temperature. For example, liquid water exhibits expansion when it is cooled below 4°C, and it keeps expanding when it is supercooled below the freezing point, 0°C. Finding a unified explanation of the anomaly of water is a long-standing challenge. It is important not only in physical chemistry but also in various other fields of science, such as biology and astronomy.

Using computer simulations Masakazu Matsumoto and his collaborators, Takuma Yagasaki and Hideki Tanaka, succeeded in detecting the molecular ordering in supercooled liquid water. Liquid water at low temperatures is not a homogeneous liquid but a dynamic aggregate of ordered nano grains. "Liquid water seems smooth and simple," says Matsumoto, an associate professor at Okayama University. "But it conceals complexity behind its appearance."

The team obtained many configurations of water molecules in by a computational technique called molecular dynamics, and analyzed the local structures in water using a pattern-matching technique. Finally, they found that the special structure named "extended polytope" is the most abundant at . This tiny and twisted structure is as stable as crystal ice and exists as nano-sized grains. The grains are chiral, i.e. there are two types of the structure that are mirror images of each other.

"Emergence of the chiral order is quite surprising," says Yagasaki, an assistant professor at Okayama University. "It has been thought that the liquid structure of water becomes ice-like when it is supercooled, but no known crystal ice possesses chirality at any length scale."

Their new analysis method enables a new way of recognizing order in the around biomolecules and in amorphous ice. The twisted structures of water might induce a new kind of interaction between the molecules dissolved in water, and might hinder ice nucleation.

"Water plays a central role in living things." says Dr. Tanaka, a professor at Okayama University. "Our discovery will allow us to reconsider the synergy between water and life from a different angle."

Explore further: How supercooled water is prevented from turning into ice

More information: Masakazu Matsumoto et al. Chiral Ordering in Supercooled Liquid Water and Amorphous Ice, Physical Review Letters (2015). DOI: 10.1103/PhysRevLett.115.197801

Related Stories

How supercooled water is prevented from turning into ice

May 21, 2015

Water behaves in mysterious ways. Especially below zero, where it is dubbed supercooled water, before it turns into ice. Physicists have recently observed the spontaneous first steps of the ice formation process, as tiny ...

Competing coexisting phases in two-dimensional water

June 17, 2016

On Earth, water is abundant substance, the cycle of evaporation - condensation - solidification (steam transitions - liquid - solid) falls within everyday experience. The physical properties of water and its phase diagram ...

Structural memory of water persists on picosecond timescale

September 18, 2015

A team of scientists from the Max Planck Institute for Polymer Research (MPI-P) in Mainz, Germany and FOM Institute AMOLF in the Netherlands have characterized the local structural dynamics of liquid water, i.e. how quickly ...

Recommended for you

Probe for nanofibers has atom-scale sensitivity

January 20, 2017

Optical fibers are the backbone of modern communications, shuttling information from A to B through thin glass filaments as pulses of light. They are used extensively in telecommunications, allowing information to travel ...

Magnetic recording with light and no heat on garnet

January 19, 2017

A strong, short light pulse can record data on a magnetic layer of yttrium iron garnet doped with Co-ions. This was discovered by researchers from Radboud University in the Netherlands and Bialystok University in Poland. ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet Feb 24, 2016
I suppose "detected" is an error in translation, perhaps a mashup of "predicted" and "deduced". A model can not "detect", in the sense of "observe". Any model prediction must be verified by observations of the REAL WORLD system being modeled for it to be accepted as accurate.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.