There may be more kinds of stuff than we thought. A team of researchers
has reported possible evidence for a new category of solids, things that
are neither pure glasses, crystals, nor even exotic quasicrystals.
Something else.
"Very weird. Strangest material I ever saw," says materials physicist
Lyle Levine of the National Institute of Standards and Technology
(NIST).
The research team from NIST and Argonne National
Laboratory has analyzed a solid alloy that they discovered in small
discrete patches of a rapidly cooled mixture of aluminum, iron and
silicon.
The material appears to have none of the extended ordering of
atoms found in crystals, which would make it a glass, except that it has
a very defined composition and grows outward from "seeds"—things that
glasses most assuredly do not do.
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| The odd microstructure of this aluminum-iron-silicon mixture is seen in this image. The round nodules are the q-glass, not crystalline but with a well-defined chemical composition. The spherical shape indicates that they grow from an initial seed. The nodules use up iron and silicon in the mixture until the surrounding concentration of aluminum gets high enough to start forming aluminum crystals, seen as long bright lines radiating from the nodules. (Color added for clarity.) (Credit: Bendersky/NIST) |
Credit: http://www.nist.gov