Featured Research

from universities, journals, and other organizations

Unusual material expands dramatically under pressure

Date:
July 18, 2013
Source:
American Crystallographic Association (ACA)
Summary:
If you squeeze a normal object in all directions, it shrinks in all directions. But a few strange materials will actually grow in one dimension when compressed. Chemists have now discovered a structure that takes this property to a new level, expanding more dramatically under pressure than any other known material.

This is a representation of zinc dicyanoaurate showing a spring-like gold helix embedded in a flexible honeycomb-like framework. (Gray balls are carbon atoms, purple is nitrogen, and teal is zinc.)
Credit: Image courtesy of Andrew Goodwin, University of Oxford.

If you squeeze a normal object in all directions, it shrinks in all directions. But a few strange materials will actually grow in one dimension when compressed. A team of chemists has now discovered a structure that takes this property to a new level, expanding more dramatically under pressure than any other known material. The finding could lead to new kinds of pressure sensors and artificial muscles.

Related Articles


Andrew Cairns, a graduate student at the University of Oxford and a member of the research team, will discuss the new material and its applications at the American Crystallographic Association meeting held July 20-24 in Honolulu.

Negative linear compression, or NLC, has existed for millions of years; in fact, biologists believe octopi and squid use the phenomenon to make their muscles contract. Only in recent decades, however, have scientists learned to design materials with this property. Until a few years ago, none of these humanmade structures had been found to expand more than a fraction of a percent under compression, making them of limited use in engineering. But researchers are now learning how to design materials that expand far more than those previously known. The trick, say the scientists presenting this latest work, is to look for structures that can respond to pressure by rearranging their atoms in space without collapsing.

The material the research team discovered, zinc dicyanoaurate, does just that. Its unique structure combines a spring-like helical chain of gold atoms embedded in a honeycomb-like framework made of gold, cyanide (carbon bonded to nitrogen), and zinc. When the chain is compressed, the honeycomb flexes outward by as much as 10% -- several times what had been achieved by any previous material. The scientists call this large response "giant negative linear compressibility," and compare it to a collapsible wine rack that folds up horizontally by expanding substantially in the vertical direction. Andrew Goodwin of Oxford, leader of the research team, says these wine rack structures represent "a new block in our Lego kit."

Zinc dicyanoaurate's unique properties make it promising for several applications. In the immediate term, the material, which is transparent, could be used as an optical pressure sensor. Compression causes the crystal spacing to narrow in one direction and widen in another, changing the path light takes through the material in a way that is sensitive to tiny variations in pressure. A longer-term application is artificial muscle design. Our muscles contract in response to an electric field, but new muscles could be designed to contract when pressure is applied, as biologists believe octopus muscles do.

Goodwin's team is now working to understand more fully the mechanisms behind NLC. But even without a complete picture of nature's design principles, they feel confident zinc dicyanoaurate is already "pushing the limits" of how far any material will be able to expand under pressure. "We've got a pretty good feel for what the limits are," Goodwin says. "This material is pretty special."


Story Source:

The above story is based on materials provided by American Crystallographic Association (ACA). Note: Materials may be edited for content and length.


Cite This Page:

American Crystallographic Association (ACA). "Unusual material expands dramatically under pressure." ScienceDaily. ScienceDaily, 18 July 2013. <www.sciencedaily.com/releases/2013/07/130718161353.htm>.
American Crystallographic Association (ACA). (2013, July 18). Unusual material expands dramatically under pressure. ScienceDaily. Retrieved November 26, 2014 from www.sciencedaily.com/releases/2013/07/130718161353.htm
American Crystallographic Association (ACA). "Unusual material expands dramatically under pressure." ScienceDaily. www.sciencedaily.com/releases/2013/07/130718161353.htm (accessed November 26, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Wednesday, November 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Who Will Failed Nuclear Talks Hurt Most?

Who Will Failed Nuclear Talks Hurt Most?

Reuters - Business Video Online (Nov. 25, 2014) With no immediate prospect of sanctions relief for Iran, and no solid progress in negotiations with the West over the country's nuclear programme, Ciara Lee asks why talks have still not produced results and what a resolution would mean for both parties. Video provided by Reuters
Powered by NewsLook.com
Flying Enthusiast Converts Real-Life Aircraft Cockpit Into Simulator

Flying Enthusiast Converts Real-Life Aircraft Cockpit Into Simulator

Reuters - Innovations Video Online (Nov. 25, 2014) A virtual flying enthusiast converts parts of a written-off Airbus aircraft into a working flight simulator in his northern Slovenian home. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
Car Park Solution for Flexible Green Energy

Car Park Solution for Flexible Green Energy

Reuters - Innovations Video Online (Nov. 24, 2014) A British solar power start-up says that by covering millions of existing car park spaces around the UK with flexible solar panels, the country's power problems could be solved. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Microsoft Adds Robot Guards, Ushers In Sci-Fi Apocalypse

Microsoft Adds Robot Guards, Ushers In Sci-Fi Apocalypse

Newsy (Nov. 23, 2014) Microsoft has robotic security guards working at its Silicon Valley Campus. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins