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arXiv · 2505.09726

Role of structural biaxiality on the phase behaviour of chiral liquid crystals

Sayantan Mondal·Jayashree Saha
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Abstract

We report a computer simulation study on the effect of molecular structural biaxiality in the phase formation of chiral molecules. In this study, we have done coarse-grained modeling to observe self-assembled phase behavior. In our molecular dynamics simulation study we varied both the chiral interaction strength and molecular biaxiality. Uniaxial molecules give rise to cholesteric phase, blue phase whereas molecular biaxiality favours cholesteric phase. At higher chirality, small chiral domains are formed creating twisted cylindrical networks with each cylinder having elliptical cross-sections instead of circular nature as found in uniaxial systems. The value of cholesteric pitch decreases when chirality and molecular biaxiality becomes higher. Coaction of biaxiality and chirality is crucial for fabricating liquid crystal materials with optical properties suitable for displays, sensors and chiral photonic devices.

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Sayantan Mondal, Jayashree Saha. 2025-05-14. Role of structural biaxiality on the phase behaviour of chiral liquid crystals. https://arxiv.org/abs/2505.09726

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