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arXiv · 2112.14607

In silico study of liquid crystalline phases formed by bent-shaped molecules with excluded-volume type interactions

Piotr Kubala·Wojciech Tomczyk·Michał Cieśla
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Abstract

We have numerically studied a liquid composed of achiral, bent-shaped molecules built of tangent spheres. The system is known to spontaneously break mirror symmetry, as it forms a macroscopically chiral, twist-bend nematic phase [Phys. Rev. Lett. 115, 147801 (2015)]. Here, we have examined the full phase diagram of such liquid and observed several phases characterized by orientational and/or translational ordering of molecules. Apart from conventional nematic, smectic A, and the above-mentioned twist-bend nematic phase, we have identified antiferroelectric smectic A phase. For large densities and a high degree of molecule's structural bend, another smectic phase emerged, where the polarization vector rotates within a single smectic layer. These results were confirmed using both Monte Carlo and molecular dynamics simulations.

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Piotr Kubala, Wojciech Tomczyk, Michał Cieśla. 2021-12-29. In silico study of liquid crystalline phases formed by bent-shaped molecules with excluded-volume type interactions. https://doi.org/10.1016/j.molliq.2022.120156

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