The Mystery of How Quasicrystals Form

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Since their invention in 1982, the external materials known as Casicrystal have been bedvils to physicists and chemists. Their atoms create patterns that are decorating themselves in the chain of Pentagon, Decagon and other sizes that never repeat. These patterns seem to deny physical law and insight. How can atoms probably “to know” how to create a broad nonpitting system without a advanced comprehension of mathematics?

“The quasicrystals are one of those topics that are the scientists of those things, when you first learn about them, you liked, ‘it’s crazy,'” ” Wenho SanA material scientist at the University of Michigan.

Although recently, a spet of the results has regained some of their privacy. In A studyThe sun and allies adopted a method to study crystals that at least some casicristal thermodynamically stable-its atoms will not be fixed in the lower-power system. This search helps explain how and why the casicristals form. Ay Second study Engineer has achieved a new way of quasicrystals and observed them in the process of formation. And there is a third research group Logged The unknown features of these abnormal materials previously.

ICally, it was challenging to create and create casicristals and create features.

“No doubt that they have interesting features,” said Sharon GlotzerA dominant physicist who is also based on the University of Michigan, but he was not involved in this work. “But to make them in large quantities, to scale them, to an industrial level -[that] It didn’t seem possible, but I think it would start to show us how it could be reproduced. “

Examples of the geometric shapes of Vikram Gavini, Summit Das, Uhayan Bike, Wenho San and Shibo Tan Geometric Size appear in casicristals. Researchers at the University of Michigan have shown that at least some of the quasicristal thermodynamically stable.

Photographs: Marsin Szequapansky Michigan Engineering

‘Forbidden’ symmetry

About a decade before Israeli physics And Shechtman The first examples of casicristals in the lab discovered, British mathematical physicist Roger Penrose “quasiperodic” – almost quite repeated – thought the patterns that would be published in these materials would be published.

Penrose Tiles It can cover an infinite aircraft without any gaps or overlap, in patterns that do not repeat and cannot. In contrast to the teselles made of triangles, rectangles and hexagons – two, three, four or six axes are symmetrical and periodic patterns – Penrose tillings have “banned” symmetry in “banned” symmetry. The tiles produce a pentagonal layout, yet the Pentagons cannot fit as well as side by side to tile the aircraft. Thus, where the tiles are five axis and the tesellets are constantly aligned, different sections of the pattern look simply similar; The correct repeat is impossible. Penrose made the cover of the caspariodic tilings Scientific American In 1977, five years ago they jumped from pure mathematics to the real world.