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Researchers at Brown University have shown a new quasi-crystal structure composed of a single nanocrystalline structure with a 10-fold rotational symmetry and non-repeatable structure.


Researchers have confirmed that a particular type of nanoparticles can self-assemble into quasicrystal superlattices. In order to fill the lattice space, the decagonal shape will bend.


The quasicrystal material was first discovered by chemist Dan Shektman in the 1980 s. In 2011, Shektman won the Nobel Prize for the discovery. The ordered structure of the crystal is repeated, but the ordered structure of the quasicrystal is not repeatable. Quasicrystals also have symmetry that does not exist in ordinary crystals. 5, 10 or 12 times symmetry in quasicrystals are "completely forbidden" in ordinary crystals.


The first quasicrystal material found is a metal alloy. Such materials have been used to make non-stick coatings for frying pans and anticorrosive coatings for surgical equipment. But interest in new quasicrystal materials puma rihanna creepers suede , especially those made of self-assembled nanoparticles, is much more. The journal (Science) reported on December 20 that the quasicrystal material family had new members. Brown University researchers in the United States had discovered a quasicrystal superlattice made of a single type of nanocrystalline building blocks. This is the first time the researchers had looked at a quasicrystal superlattice made up of a single component. The results can provide new insights into the formation of quasi-crystal structures. Ou Chen, assistant professor of chemistry at Brown University and lead author of the paper, said: "although scientists have predicted single component quasicrystal lattices through mathematical and computer simulations, there has been no laboratory evidence. We have obtained a new type of quasicrystal puma rihanna creepers norge , and we have found the rules for its preparation. This will have a profound impact on the study of crystal structure. "


About two years ago, Chen designed a new type of nanocrystalline building block: pyramidal tetrahedron quantum dots. Although most of the studies on nanocrystalline structures were carried out with spherical gold nanoparticles, Chen's tetrahedron structure was more compact and may form more rigid and complex structures. Another key feature of this nanoblock was its anisotropy. The surface of each pyramidal particle corresponded to a different ligand. When particles were assembled into larger structures, surfaces with similar ligands tended to bind to each other. Compared with anisotropic particles, the directional bond made the structure more interesting and complex. In a recent paper published in the journal Nature yeezy boost 350 v2 norge , Chen's team reported on the most complex superstructure ever constructed of nanoparticles, which were actually quasilattices. "when I realized it was quasicrystal, I immediately sent an email to Chen," said Yasutaka Nagaoka, a postdoctoral scholar and lead author of the paper.


Using transmission electron microscopy yeezy boost 350 svart , the researchers showed the discrete decagonal shape assembled by the particles and the quasi-lattice with 10 times rotational symmetry. By analyzing the structure of quasicrystals, researchers had discovered a new rule for forming quasicrystals, which was called the "flexible polygon tile rule". Chen believed that this rule would be helpful to the further study of quasicrystal structure and provided new information for material science, chemistry, mathematics and even art design.