Featured Research

from universities, journals, and other organizations

Probing hydrogen under extreme conditions

Date:
April 13, 2012
Source:
Carnegie Institution
Summary:
How hydrogen -- the most abundant element in the cosmos -- responds to extremes of pressure and temperature is one of the major challenges in modern physical science. Moreover, knowledge gleaned from experiments using hydrogen as a testing ground on the nature of chemical bonding can fundamentally expand our understanding of matter. New work has enabled researchers to examine hydrogen under pressures never before possible.

How hydrogen--the most abundant element in the cosmos--responds to extremes of pressure and temperature is one of the major challenges in modern physical science. Moreover, knowledge gleaned from experiments using hydrogen as a testing ground on the nature of chemical bonding can fundamentally expand our understanding of matter. New work from Carnegie scientists has enabled researchers to examine hydrogen under pressures never before possible.

Their work is published online in Physical Review Letters.

To explore hydrogen in this new domain, the scientists developed new techniques to contain hydrogen at pressures of nearly 3 million times normal atmospheric pressure (300 Gigapascals) and to probe its bonding and electronic properties with infrared radiation. They used a facility that Carnegie manages and operates at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory in partnership with NSLS. Observing hydrogen's behavior under very high pressures has been a great challenge for researchers, because it is in a gas state under normal conditions. It is known that it has three solid molecular phases. But the structures and properties of highest-pressure phases are unknown.

For example, a transition to a phase that occurs at about 1.5 million times atmospheric pressure (150 Gigapascals) and at low temperatures has been of particular interest. But there have been technological hurdles in examining hydrogen at much higher pressures using static compression techniques. It has been speculated that under at high pressures, hydrogen transforms to a metal, which means it conducts electricity. It could even become a superconductor or a superfluid that never freezes--a completely new and exotic state of matter. In this new work, the research team, which included Carnegie's Chang-sheng Zha, Zhenxian Liu, and Russell Hemley, developed new techniques to measure hydrogen samples at pressures above 3 million times normal atmospheric pressure (above 300 Gigapascals) and at temperatures ranging from -438 degrees Fahrenheit (12 Kelvin) to close to room temperature..

"These new static compression techniques have opened a window on the behavior of hydrogen at never-before-reached static pressures and temperatures," said Hemley, director of the Geophysical Laboratory. The team found that the molecular state was stable to remarkably high pressures, confirming extraordinary stability of the chemical bond between the atoms. Their work disproves the interpretations of experiments by other researchers reported last year indicating a metallic state under these conditions. Evidence for semimetallic behavior in the dense molecular phase was found in the new study, but the material must have electrical conductivity well below that of a full metal.

Meanwhile, in another paper also published in Physical Review Letters, a team from the University of Edinburgh and including Carnegie's Alexander Goncharov report evidence for another phase of molecular hydrogen. They found it at the relatively high temperature of 80 degrees Fahrenheit (300 Kelvin) and under pressures above 220 Gigapascals. They suggest that the structure of hydrogen in this new phase is a honeycomb made of six-atom rings, similar to the carbon structure of graphene.


Story Source:

The above story is based on materials provided by Carnegie Institution. Note: Materials may be edited for content and length.


Journal Reference:

  1. Chang-Sheng Zha, Zhenxian Liu, Russell Hemley. Synchrotron Infrared Measurements of Dense Hydrogen to 360GPa. Physical Review Letters, 2012; 108 (14) DOI: 10.1103/PhysRevLett.108.146402

Cite This Page:

Carnegie Institution. "Probing hydrogen under extreme conditions." ScienceDaily. ScienceDaily, 13 April 2012. <www.sciencedaily.com/releases/2012/04/120413101343.htm>.
Carnegie Institution. (2012, April 13). Probing hydrogen under extreme conditions. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2012/04/120413101343.htm
Carnegie Institution. "Probing hydrogen under extreme conditions." ScienceDaily. www.sciencedaily.com/releases/2012/04/120413101343.htm (accessed July 24, 2014).

Share This




More Matter & Energy News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
Powered by NewsLook.com
Boeing Ups Outlook on 52% Profit Jump

Boeing Ups Outlook on 52% Profit Jump

Reuters - Business Video Online (July 23, 2014) Commercial aircraft deliveries rose seven percent at Boeing, prompting the aerospace company to boost full-year profit guidance- though quarterly revenues missed analyst estimates. Bobbi Rebell reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Car Market on the Rebound?

Europe's Car Market on the Rebound?

Reuters - Business Video Online (July 23, 2014) Daimler kicks off a round of second-quarter earnings results from Europe's top carmakers with a healthy set of numbers - prompting hopes that stronger sales in Europe will counter weakness in emerging markets. Hayley Platt reports. Video provided by Reuters
Powered by NewsLook.com
9/11 Commission Members Warn of Terror "fatigue" Among American Public

9/11 Commission Members Warn of Terror "fatigue" Among American Public

Reuters - US Online Video (July 22, 2014) Ten years after releasing its initial report, members of the 9/11 Commission warn of the "waning sense of urgency" in combating terrorists attacks. Mana Rabiee reports. Video provided by Reuters
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:
from the past week

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