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Formation of the Smectic-B Crystal from a Simple Monatomic Liquid

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 نشر من قبل Tomas Oppelstrup
 تاريخ النشر 2013
  مجال البحث فيزياء
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We report a molecular dynamics simulation demonstrating that the Smectic B crystalline phase (Cr-B), commonly observed in mesogenic systems of anisotropic molecules, can be formed by a system of identical particles interacting via a spherically symmetric potential. The Cr-B phase forms as a result of a first order transition from an isotropic liquid phase upon isochoric cooling at appropriate number density. Its structure, determined by the design of the pair potential corresponds to Cr-B structure formed by elongated particles with the aspect ratio 1.8. The diffraction pattern, and the real-space structure inspection demonstrate dominance of the ABC-type of axial layer stacking. This result opens a general possibility of producing smectic phases using isotropic interparticle interaction both in simulations and in colloidal systems.

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