Subscribe to our free daily newsletters
. 24/7 Space News .




Subscribe to our free daily newsletters



TECH SPACE
Melting solid below the freezing point
by Staff Writers
Washington DC (SPX) Jan 24, 2017


When a crystal structure of bismuth (right) is decompressed from 32,000 atmospheres (3.2 GPa) to 12,000 atmospheres (1.2 GPa) it melts into a liquid at about 23,000 atmospheres (2.3 GPa) (middle). It then recrystallizes at 12,000 atmospheres (left). The so-called metastable liquid produced by this decompression occurs in a pressure-temperature range similar to where the supercooled bismuth is produced. Supercooled liquids are cooled below the freezing point without turning into a solid or a crystal. Image courtesy Chuanlong Lin and Guoyin Shen, Carnegie Institution.

Phase transitions surround us - for instance, liquid water changes to ice when frozen and to steam when boiled. Now, researchers at the Carnegie Institution for Science* have discovered a new phenomenon of so-called metastability in a liquid phase. A metastable liquid is not quite stable.

This state is common in supercooled liquids, which are liquids that cool below the freezing point without turning into a solid or a crystal. Now, scientists report the first experimental evidence of creating a metastable liquid directly by the opposite approach: melting a high-pressure solid crystal of the metal bismuth via a decompression process below its melting point.

The results, reported in the January 23, 2017, issue of Nature Communications, could be important for developing new materials and for understanding the dynamics of planetary interiors, such as earthquakes, because a metastable liquid could act as a lubricant strongly affecting the dynamics of the Earth's interior.

"Phase transitions come in two basic 'flavors,'" explained Carnegie co-author Guoyin Shen, director of the High-Pressure Collaborative Access Team at the Advanced Photon Source*.

"In one type, the chemical bonds do not break as the material goes from one phase to another. But they do alter in orientation and length in an orderly manner. The other, called reconstructive phase transition, is more chaotic, but the most prevalent in nature and the focus of this study. In these transitions, parts of the chemical bonds are broken and the structure changes significantly when it enters a new phase."

Pressure can be used to change the phase of a material in addition to heating and cooling. The scientists put a form of crystalline bismuth in a pressure-inducing diamond anvil cell, and subjected it to pressures and decompression ranging from 32,000 times atmospheric pressure (3.2 GPa) to 12,000 atmospheres (1.2 GPa) at a temperature of 420F (489 K). Under decompression only, at about 23,000 atmospheres, bismuth melts into a liquid. Then at 12,000 atmospheres it recrystallizes.

"The richness in crystalline structure of bismuth is particularly useful for witnessing changes in the structure of a material," remarked lead author Chuanlong Lin.

The researchers imaged the changes using a technique called X-ray diffraction, which uses much higher energy X-rays than those we use for medical imaging and can therefore discern structure at the atomic level. They conducted five different compression/decompression rounds of experiments.

"The bismuth displayed a metastable liquid in the process of solid-solid phase transitions under decompression at about 23,000 to 15,000 atmospheres," Lin said.

The scientists also found that the metastable state can endure for hours below the melting point under static conditions. Interestingly, the metastable liquid produced by decompression occurred in a pressure-temperature range that is similar to where supercooled bismuth is produced.

"Because reconstructive phase transitions are the most fundamental type, this research provides a brand new way for understanding how different materials change," Shen said.

"It's possible that other materials could display a similar metastable liquid when they undergo reconstructive transitions and that this phenomenon is more prevalent than we thought. The results will no doubt lead to countless surprises in both materials science and planetary science in the coming years."

Research paper


Comment on this article using your Disqus, Facebook, Google or Twitter login.


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only

.


Related Links
Carnegie Institution for Science
Space Technology News - Applications and Research






Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Previous Report
TECH SPACE
The power of attraction
Thuwal, Saudi Arabia (SPX) Jan 18, 2017
Engineered nanometer- and micrometer-scale structures have a vast array of uses in electronics, sensors and biomedical applications. Because these are difficult to fabricate, KAUST researchers are trying a bottom-up philosophy, which harnesses the natural forces between atoms and molecules such that microstructures form themselves. This approach, a departure from the usual top-down approac ... read more


TECH SPACE
Mister Trump Goes to Washington

NASA to rely on Soyuz for ISS missions until 2019

Lomonosov Moscow State University to Launch 'Space Department' in 2017

French, US astronauts install batteries outside space station

TECH SPACE
ULA and team launches US military spy satellite

Airbus Safran Launchers in 2016: we keep our promises

India Defers Much-Awaited Heaviest Rocket Launch

When One launch is not enough: SpaceX Return To Flight

TECH SPACE
Bursts of methane may have warmed early Mars

Long Eclipse Avoidance Manoeuvres Performed Successfully on MOM Spacecraft

Microbes could survive thin air of Mars

Mars rover Opportunity takes a drive up a steep slope

TECH SPACE
China's first cargo spacecraft to leave factory

China launches commercial rocket mission Kuaizhou-1A

China Space Plan to Develop "Strength and Size"

Beijing's space program soars in 2016

TECH SPACE
ESA Planetary Science Archive gets a new look

Iridium-1 NEXT Launched on a Falcon 9

Shaping the Future: Aerospace Works to Ensure an Informed Space Policy

Russia-China Joint Space Studies Center May Be Created in Southeastern Russia

TECH SPACE
New white paper reviews latest support for Redefinition of the Kilogram by 2018

A new approach to 3-D holographic displays greatly improves the image quality

Melting solid below the freezing point

New class of materials could revolutionize biomedical, alternative energy industries

TECH SPACE
First footage of a living stylodactylid shrimp filter-feeding at depth of 4826m

SF State astronomer searches for signs of life on Wolf 1061 exoplanet

Looking for life in all the right places with the right tool

Could dark streaks in Venusian clouds be microbial life

TECH SPACE
Public to Choose Jupiter Picture Sites for NASA Juno

Experiment resolves mystery about wind flows on Jupiter

Pluto Global Color Map

Lowell Observatory to renovate Pluto discovery telescope




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News






The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement