Can off-centre mesogen dipoles extend the biaxial nematic range?

نویسندگان

  • Lara Querciagrossa
  • Roberto Berardi
  • Claudio Zannoni
چکیده

We have investigated the possibility of extending the stability range of the biaxial nematic phase by adding an off-centre dipole of various strengths and orientations to elongated biaxial Gay-Berne (GB) mesogens yielding a relatively narrow biaxial nematic (Nbx) phase, and a smectic (Sbx) phase when dipole-less. The effect of dipoles is not easy to predict, and our previous investigations have shown the limited benefits of having a central dipole. Here we show, employing molecular dynamics (MD) simulations, that a not too strong off-centre dipole positioned along the longest axis of the nematogen can extend the temperature range of stability of the biaxial nematic phase, also shifting it towards lower temperatures.

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عنوان ژورنال:
  • Soft matter

دوره 14 12  شماره 

صفحات  -

تاریخ انتشار 2018