Scientists create one-dimensional ferroelectric ice

Scientists create one-dimensional ferroelectric ice
Models of (A) water molecules in a nanochannel at 300 K, (B) 1D ice in an external electric field whose direction is to the left, and (C) 1D ice in an external electric field whose direction is to the right. In B and C, the red and green balls represent oxygen and hydrogen atoms, respectively, and the orange dashed lines represent hydrogen bonds. Image credit: Hai-Xia Zhao, et al. ©2011 PNAS.

( -- Everyone knows that when water freezes, it forms ice. But a lesser known fact is that there is not one, but many different kinds of ice, depending on the way the ice crystals are arranged. In a new study, a team of chemists has developed a new method for synthesizing a type of ferroelectric ice, which is crystallized so that all of its bonds line up in the same direction, producing a large electric field.

The researchers, including Hai-Xia Zhao, Xiang-Jian Kong and La-Sheng Long, along with their coauthors from Xiamen University in Xiamen, China, and Hui Li and Xiao Cheng Zeng from the University of Nebraska in the US, have published their study in a recent issue of the .

Every molecule carries a tiny electric field. But because usually freeze in a somewhat random arrangement, with their bonds pointing in different directions, the ice’s total electric field tends to cancel out. In contrast, the bonds in ferroelectric ice all point in the same direction at low enough temperatures, so that it has a net polarization in one direction that produces an electric field.

Ferroelectric ice is thought to be extremely rare; in fact, scientists are still investigating whether or not pure three-dimensional ferroelectric ice exists in nature. Some researchers have proposed that ferroelectric ice may exist on Uranus, Neptune, or Pluto. Creating pure 3D ferroelectric ice in the laboratory seems next to impossible, since it would take an estimated 100,000 years to form without the assistance of catalysts. So far, all ferroelectric ices produced in the laboratory are less than three dimensions and in mixed phases (heterogeneous).

In the new study, the scientists have synthesized a one-dimensional, single-phase (homogeneous) ferroelectric ice by freezing a one-dimensional water ‘wire.’ As far as the scientists know, this is the first single-phase ferroelectric ice synthesized in the laboratory.

To create the water wire, the researchers designed very thin nanochannels that can hold just 96 H2O molecules per crystalline unit cell. By lowering the temperature from a starting point of 350 K (77°C, 171°F), they found that the water wire undergoes a phase transition below 277 K (4°C, 39°F), transforming from 1D liquid to 1D ice. The ice also exhibits a large dielectric anomaly at this temperature and at 175 K (-98°C, -144°F).

“We know the freezing point should be different from normal water because the water is confined to nanochannels and not in a normal environment,” Zeng told “Why 1D water has a higher temperature in this case is still an open question.”

As the scientists explained, the hydrogen-bonding interactions among H20 molecules in the water wire and the nanochannel play an important role in the ferroelectricity of the ice. While the hydrogen bonds between the water and nanochannel do not break, the remaining hydrogen atoms in the ice rotate under an opposite electric field. As a result, the polarity of the ferroelectric ice can be reversed by reversing the external , a property not seen in everyday water and ice.

Overall, the production of a 1D, single-phase ferroelectric ice using water confined to a nanochannel provides a new way to synthesize ferroelectric materials. The new method could also help scientists better understand the unique properties of ferroelectric ice, which could have applications in the biological sciences, geoscience, and nanoscience. As Zeng noted, ferroelectric could potentially have electrical applications, with the efforts of engineers working in nanotechnology.

“[The study] shows that the freezing of water can be greatly affected by the confinement and water/surface interaction,” Zeng said. “So knowledge and insights gained through research in this field will help scientists to control some properties of water through designing different confinements.”

Explore further

Reverse Chemical Switching of a Ferroelectric Film

More information: Hai-Xia Zhao, et al. “Transition from one-dimensional water to ferroelectric ice within a supramolecular architecture.” PNAS Early Edition. DOI:10.1073/pnas.1010310108

Copyright 2010
All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of

Citation: Scientists create one-dimensional ferroelectric ice (2011, February 25) retrieved 23 October 2019 from
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Feedback to editors

User comments

Feb 25, 2011
This is so reminiscent of the concept of 'ice nine' from the Kurt Vonnegut novel Cats Cradle. Check it out.

Feb 25, 2011
This comment has been removed by a moderator.

Feb 25, 2011
@zslewis91 and @dansmithillustration

From wikipedia:

Ice IX - A tetragonal phase. Formed gradually from ice III by cooling it from 208 K to 165 K, stable below 140 K and pressures between 200 MPa and 400 MPa. It has density of 1.16 g/cm3, slightly higher than ordinary ice.

Feb 25, 2011
The Ice IX phase does exists, but is not the same IceIX in the movies

Feb 27, 2011
movies? hes talking about a book, and a good one at that. read something by kurt vonnegut its really good

Feb 27, 2011
...from Kurt Vonnegut's "Cat's Cradle":
"There are several ways," Dr. Breed said to me, "in which certain liquids can crystallize — can freeze — several ways in which their atoms can stack and lock in an orderly, rigid way."

That old man with spotted hands invited me to think of the several ways in which cannonballs might be stacked on a courthouse lawn, of the several ways in which oranges might be packed into a crate.

"So it is with atoms in crystals, too; and two different crystals of the same substance can have quite different physical properties."

"Now suppose," chortled Dr. Breed, enjoying himself, "that there were many possible ways in which water could crystallize, could freeze. Suppose that the sort of ice we skate upon and put into highballs — what we might call ice-one — is only one of several types of ice. Suppose water always froze as ice-one on Earth because it had never had a seed to teach it how to form ice-two, ice-three, ice-four … ?

Feb 27, 2011
We are making new compound arrangements all the time, nothing new there. Whats new is the properties of these strange synthetic compounds and what they can do.

If anyone knows of a compound table with all these new discoveries, starting at the periodic table and combining the elements with each other in ever weirder combinations that would be interesting.

Remember old Buckyballs and the surprise when they discovered carbon can form a new arrangement, magical hysteria thats what. "They'll be building sky scrapers out of the stuff soon..' they said.

Feb 28, 2011
Gee, I was taught is High School Chemistry that water is necessarily a 3D molecule, due to the unbonded pairs on the oxygen. If you can make them get in the same plane with all the nuclei without changing the fundamental chemistry of the atoms, then I'll be impressed.

Feb 28, 2011
Surely 1D is a single point in space, not a plane or a line. Wouldn't 1D ice be 1 molecule of ice (ie, not ice)?

Feb 28, 2011
Gee, I was taught is High School Chemistry that water is necessarily a 3D molecule, due to the unbonded pairs on the oxygen. If you can make them get in the same plane with all the nuclei without changing the fundamental chemistry of the atoms, then I'll be impressed.

I was going to be like "WTF how are you not impressed". But I decided to keep the negativity off the board.

Mar 04, 2011
I think 1D is the wrong way to describe it. It's really 2D and no thicker than an atom. At least that's what I'm gathering. And yes everyone.. technically it is 3D, but 3D in the way a sheet of paper is. For all practical purposes it's 2D. Even a line on a piece of paper is 3D if you want to get technical. All those layers of graphite... but let's cut some slack here, and take it for what it is. An amazing idea that's been synthesized (albeit on a small scale) in a lab.

Mar 05, 2011
The temperature rise in a more restrained environment of degrees of freedom is unusual. Perhaps ar such low number of molecular width of the channel, the nano-tube design material characteristics at the surface interaction predominate in the electro-polarization, robbing degrees of bond motion through electrostatics at molecular interface levlels and imperfections in nano-contour, or the actual EM field induced constrains some degrees of enrgy ensorbing motion/energy content. The electrical resistivity may also be adding to the higher temp. A model may be altered, if nano tubular material matrix is chosen from a hydrphobic vs hydrophyllic compound, or a chargeable substance through electrostatics or applied field current. Trans-axis magnetic fields as probes and as matrix energy modifiers may reveal some interactions.
Of interest would be ice linearity changes with further Temp drop, or hydrostatic pressure(aqueous/non-aqueus),as extrusion/bundling compression testing in E Field.

Mar 05, 2011
You're not dealing with water or ice. They require minimal molecule #s in cross sections for material properties of plasticity, averaged crystalline forces/orders, and dissemination of net elctrostatic fields and net averaged covalent bond fields.You are measuring Hydroxy-hydrogen lamina/threads-different field distributions with way exagerated matrix/tube wall % interactivity and tube wall field permeation into the thread. No surface tensile/field bonding-weak or small, characteristic of Ice(H2O-minimal molecular depth)apply here as the degreees of freedom of motion/energy absorption of thin thread exponentially different in terms of boundary interaction, energy absorption and heat content. Its a new material. Same for floating a battleship in a gallon of water/rubber duck in teaspoon of water. It ain't water when it's spread that thin.

Mar 06, 2011
There are in fact many forms of ice that have varying crystal structures. Most are only stable at low temperatures and high pressures, not including amorphous ice that is glassy in 'structure'. It would be interesting to know how other properties of the 1D ferroelectric ice are altered.

Kidane makes some very important points. The chains of water molecules do not represent 'water' in any group chemical sense. Water molecule to host lattice interactions, particularly in the complex organic matrix, will have major impacts on the 1D chains.

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