Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Unusual material expands dramatically under pressure

19.07.2013
Surprising property, presented at the American Crystallographic Association Meeting in Hawaii, could aid in the design of pressure sensors and artificial muscles

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.


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.

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 manmade 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."

The presentation 13.06.8, "Pushing the limits: giant negative linear compressibility," will take place from 11:15-11:30 am on Monday, July 22. Abstract: http://www.amercrystalassn.org/app/session/100136

Catherine Meyers | EurekAlert!
Further information:
http://www.aip.org

More articles from Materials Sciences:

nachricht InLight study: insights into chemical processes using light
05.12.2016 | Fraunhofer-Institut für Lasertechnik ILT

nachricht Physics, photosynthesis and solar cells
01.12.2016 | University of California - Riverside

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

IHP presents the fastest silicon-based transistor in the world

05.12.2016 | Power and Electrical Engineering

InLight study: insights into chemical processes using light

05.12.2016 | Materials Sciences

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>