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arXiv · 2608.20957

Broken Inversion Symmetry via a Magic Methyl Effect

Calum J Gibb·Jordan Hobbs·Caitlin O Brien·Kate Hille·Benji Maher·Christopher M Pask·Richard J Mandle
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Abstract

Polar liquid crystals - fluid phases in which molecular dipoles organise into ferro- or antiferroelectric states - present a highly constrained molecular design space, where small changes can entirely suppress polar organisation. Here we demonstrate, contrary to expectations, that installation of a methyl group in the 5-position of a 1,3-dioxane ring substantially increases the onset temperature of polar order. Remarkably, this effect proves transferable across several liquid-crystal families, including examples where the methylated derivative exhibits a polar phase whereas its parent compound does not. Across 8 matched pairs, we find that a 5-methyl group can enhance the onset temperature of polar order in 1,3-dioxane materials by up to 120 {\deg}C. These findings establish a simple and general molecular design strategy for enhancing and enabling spontaneous dipolar ordering in liquid crystals.

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Calum J Gibb, Jordan Hobbs, Caitlin O Brien, Kate Hille, Benji Maher, Christopher M Pask, Richard J Mandle. 2026-08-21. Broken Inversion Symmetry via a Magic Methyl Effect. https://arxiv.org/abs/2608.20957

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