Scientists from Ames Laboratory and Iowa State University carrying out research at the X-ray Science Division (XSD) beamline 6-ID-D at the U.S. Department of Energy Office of Science’s Advanced Photon Source (APS) at Argonne characterized a new family of rare-earth quasicrystals. They are candidates for applications from hydrogen storage, to cylinder liners and piston coatings that could reduce air pollution and increase engine lifetimes, to coatings on metallic parts for bone repair and prostheses.

These are the only known magnetic rare-earth icosahedral binary quasicrystals. They constitute a ​“matched set” of magnetic quasicrystals and their closely related periodic cousins, providing a means for cleaner comparison of structural and magnetic properties between a quasicrystal and its periodic approximant.

High-energy x-ray single-crystal diffraction was employed at X-ray Science Division (XSD) beamline 6-ID-D to characterize and index diffraction patterns from several of the rare-earth icosahedral binary quasicrystals discovered by the researchers.

The team subsequently returned to XSD 6-ID-D and utilized x-rays from the new APS superconducting undulator to obtain a diffraction pattern from an icosahedral Gd-Cd quasicrystal showing 10-fold rotational symmetry.  This diffraction pattern is the cover illustration for the latest issue of Nature Materials (right).

Reference: A.I. Goldman, T. Kong, A. Kreyssig, A. Jesche, M. Ramazanoglu, K.W. Dennis, S.L. Bud’ko, and P.C. Canfield, ​“A family of binary magnetic icosahedral quasicrystals based on rare earths and cadmium,” Nat. Mater. 12, 714 (2013). DOI:10.1038/nmat3672

Contact: goldman@​ameslab.​gov, canfield@​ameslab.​gov, lang@​aps.​anl.​gov

See also: Nature Materials News & Views article, ​“Quasicrystals: Model structures,” by Marc de Boissieu, which can be read here; and the APS science and research highlight found here.