Printer Friendly

A new family of stable quasicrystals.

A new family of stable quasicrystals

Under the right conditions, atoms in an aluminum-manganese alloy may line up into an arrangement that doesn't repeat itself at regular intervals yet appears to have the orderliness of a crystalline substance. Such a material, known as a quasiperiodic crystal, or quasicrystal, generally has an electron diffraction pattern that shows a fivefold symmetry. Ever since the discovery of the first quasicrystalline alloy, researchers have been looking for other materials with similar properties (SN: 3/7/87, p. 152).

The latest addition to the quasicrystal family is an alloy made from gallium, magnesium and zinc. First prepared by Wataru Ohashi and Frans Spaepen of Harvard University, the samples are made up of icosahedral crystals as large as 100 microns across. Unlike all but one previously discovered quasicrystalline material, this alloy is stable. Heating doesn't transform it into a periodic crystal structure.

"The discovery of a second stable quasiperiodic crystal will be of interest for diffraction studies of the structure and defects of these phases," the researchers report in the Dec. 10 NATURE. "Their low melting temperatures and the chemical behavior of the alloys make the crystals quite easy to prepare."
COPYRIGHT 1988 Science Service, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1988, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

Article Details
Printer friendly Cite/link Email Feedback
Publication:Science News
Date:Jan 2, 1988
Previous Article:A ceramic that goes with the flow.
Next Article:Sun-powered, long-distance chemistry.

Related Articles
Quasicrystals: a new ordered structure.
Probing deeper into quasicrystals.
Bigger and better quasicrystals.
Shaking up quasicrystals.
Taking the fuzziness out of quasicrystals.
Tilings for picture-perfect quasicrystals.
Clusters and decagons: new rules for constructing a quasicrystal.
Special steel finds real applications.
A Quasicrystal Construction Kit.

Terms of use | Copyright © 2017 Farlex, Inc. | Feedback | For webmasters