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Posts Tagged ‘quasicrystal

Further proof of extraterrestrial origin of quasicrystals

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Fragment of a 3D icosahedral quasicrystal composed of four types of polyhedral units. (Courtesy: J E S Socolar, P Steinhardt)

An international team of researchers has found nine new samples of naturally occurring quasicrystals. The work also provides further proof that quasicrystals were delivered to the Earth by a meteorite. The team’s discovery challenges our understanding of both crystallography and solar-system formation.
Conventional crystal structures are made of atoms, or clusters of atoms, that repeat periodically. These patterns are normally restricted to two, three, four or sixfold rotational symmetry – the numbers corresponding to how many times the crystal appears the same during a rotation through 360°. For a long time these were considered hard and fast rules, and no crystals that broke these conditions were thought to exist…..
Read more at: physicsworld.com

Written by physicsgg

August 13, 2012 at 6:33 pm

Posted in Chemistry

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Nobel prizewinning quasicrystal fell from space

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It came from outer space (Image: Luca Bindi and Paul Steinhardt)

A Nobel prizewinning crystal has just got alien status. It now seems that the only known sample of a naturally occurring quasicrystal fell from space, changing our understanding of the conditions needed for these curious structures to form….
Read more: newscientist.com

Read also: The quasicrystal from outer space

Written by physicsgg

January 3, 2012 at 5:04 pm

Posted in Chemistry, SPACE

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