Biaxial nematic phase in model bent-core systems.

نویسندگان

  • Piotr Grzybowski
  • Lech Longa
چکیده

We determine the bifurcation phase diagrams with isotropic (I), uniaxial (N(U)) and biaxial (N(B)) nematic phases for model bent-core mesogens using Onsager-type theory. The molecules comprise two or three Gay-Berne interacting ellipsoids of uniaxial and biaxial shape and a transverse central dipole. The Landau point is found to turn into an I-N(B) line for the three-center model with a large dipole moment. For the biaxial ellipsoids, a line of Landau points is observed even in the absence of the dipoles.

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عنوان ژورنال:
  • Physical review letters

دوره 107 2  شماره 

صفحات  -

تاریخ انتشار 2011