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arXiv · 0902.0671

Chiral Symmetry Breaking in Bent-Core Liquid Crystals

Lech Longa·Grzegorz Pająk·Thomas Wydro
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Abstract

By molecular modeling we demonstrate that the nematic long-range order discovered in bent-core liquid crystal systems should reveal further spatially homogeneous phases. Two of them are identified as a tetrahedratic nematic ($N_T$) phase with $D_{2d}$ symmetry and a chiral tetrahedratic nematic ($N_T^*$) phase with $D_2$ symmetry. These new phases were found for a lattice model with quadrupolar and octupolar anisotropic interactions using Mean Field theory and Monte Carlo simulations. The phase diagrams exhibit tetrahedratic ($T$), $N_T$ and $N_T^*$ phases, in addition to ordinary isotropic ($I$), uniaxial nematic ($N_U$) and biaxial nematic ($N_B$) phases. To our knowledge, this is the first molecular model with spontaneous chiral symmetry breaking in non-layered systems.

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Lech Longa, Grzegorz Pająk, Thomas Wydro. 2009-02-04. Chiral Symmetry Breaking in Bent-Core Liquid Crystals. https://doi.org/10.1103/physreve.79.040701

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