Featured Research

from universities, journals, and other organizations

Scientists Resolve 60-year-old Plutonium Questions

Date:
June 7, 2006
Source:
Lawrence Livermore National Laboratory
Summary:
Scientists have solved a question about the nature of plutonium that has remained a mystery since the Manhattan Project. Plutonium behaves like no other element in nature. The bonding of its electrons causes its crystal structure to be uneven, similar to a mineral, and the nucleus is unstable, causing the metal to spontaneously decay over time and damage the surrounding metal lattice.

A plutonium-gallium alloy ingot reclaimed from a nuclear weapon.
Credit: Image courtesy of Lawrence Livermore National Laboratory

Scientists have gone a long way to solving a question about the nature of plutonium that has remained a mystery since the Manhattan Project.

Plutonium behaves like no other element in nature. The bonding of its electrons causes its crystal structure to be uneven, similar to a mineral, and the nucleus is unstable, causing the metal to spontaneously decay over time and damage the surrounding metal lattice.

First batches of the metal were too brittle to machine due to the mineral-like structure of the crystal. In order to make the metal machinable, the high-temperature, high-symmetry cubic structure of plutonium needed to be retained to room temperature.

Scientists during the Manhattan Project achieved this by adding a small amount of gallium.

There was never a clear explanation as to why gallium stabilized the ductile cubic structure over the low-symmetry mineral-like structure; they just did it and it worked, said Kevin Moore, a staff scientist in the Materials Science and Technology Division at Lawrence Livermore National Laboratory.

For the first time, researchers have determined why gallium works. In pure plutonium, the bonds between Pu atoms are very uneven, causing the metals high propensity to adopt a low-symmetry structure. However, when a gallium atom is put in the plutonium lattice, it causes the bonds to become more uniform and thus leads to the high-symmetry cubic structure.

Gallium evens out the plutonium bonds, Moore said. The calculations strongly illuminate why gallium stabilizes the machinable cubic structure to room temperature.

Through a series of calculations, Moore and his Livermore colleagues, Per Sφderlind and Adam Schwartz, and David Laughlin of Carnegie Mellon University have produced results that appear in the May 26 online edition of Physical Review Letters.

The team next proposes to test their calculations in the laboratory.

Founded in 1952, Lawrence Livermore National Laboratory has a mission to ensure national security and apply science and technology to the important issues of our time. Lawrence Livermore National Laboratory is managed by the University of California for the U.S. Department of Energy’s National Nuclear Security Administration.


Story Source:

The above story is based on materials provided by Lawrence Livermore National Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

Lawrence Livermore National Laboratory. "Scientists Resolve 60-year-old Plutonium Questions." ScienceDaily. ScienceDaily, 7 June 2006. <www.sciencedaily.com/releases/2006/06/060607084030.htm>.
Lawrence Livermore National Laboratory. (2006, June 7). Scientists Resolve 60-year-old Plutonium Questions. ScienceDaily. Retrieved April 17, 2014 from www.sciencedaily.com/releases/2006/06/060607084030.htm
Lawrence Livermore National Laboratory. "Scientists Resolve 60-year-old Plutonium Questions." ScienceDaily. www.sciencedaily.com/releases/2006/06/060607084030.htm (accessed April 17, 2014).

Share This



More Matter & Energy News

Thursday, April 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

German Researchers Crack Samsung's Fingerprint Scanner

German Researchers Crack Samsung's Fingerprint Scanner

Newsy (Apr. 16, 2014) — German researchers have used a fake fingerprint made from glue to bypass the fingerprint security system on Samsung's new Galaxy S5 smartphone. Video provided by Newsy
Powered by NewsLook.com
Porsche CEO Says Supercar Is Not Dead: Cue the Spyder 918

Porsche CEO Says Supercar Is Not Dead: Cue the Spyder 918

TheStreet (Apr. 16, 2014) — The Porsche Spyder 918 proves that, in an automotive world obsessed with fuel efficiency, the supercar is not dead. Porsche North America CEO Detlev von Platen attributes the brand's consistent sales growth -- 21% in 2013 -- with an investment in new technology and expanded performance dynamics. The hybrid Spyder 918 has 887 horsepower and 944 lb-ft of torque, but it can run 18 miles on just an electric charge. The $845,000 vehicle is not a consumer-targeted vehicle but a brand statement. Video provided by TheStreet
Powered by NewsLook.com
Industry's Optimism Shines At New York Auto Show

Industry's Optimism Shines At New York Auto Show

Newsy (Apr. 16, 2014) — After seeing auto sales grow last month, there's plenty for the industry to celebrate as it rolls out its newest designs. Video provided by Newsy
Powered by NewsLook.com
Ford Mustang Fetes Its 50th Atop Empire State Building

Ford Mustang Fetes Its 50th Atop Empire State Building

AFP (Apr. 16, 2014) — Ford celebrated the 50th birthday of its beloved Mustang by displaying a new model of the convertible on top of the Empire State Building in New York. Duration: 00:28 Video provided by AFP
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