On the emergence of molecular tilt in a ferroelectric smectic liquid crystal with broken director-inversion symmetry

Aitor Erkoreka; Mauricio Vera-Arévalo; Alberto Concellón; Sergio Diez-Berart; Jordi Sellarès; Adrià Gràcia-Condal; Ibon Alonso; Josu Martinez-Perdiguero

arXiv · 2606.18870

On the emergence of molecular tilt in a ferroelectric smectic liquid crystal with broken director-inversion symmetry

Aitor Erkoreka·Mauricio Vera-Arévalo·Alberto Concellón·Sergio Diez-Berart·Jordi Sellarès·Adrià Gràcia-Condal·Ibon Alonso·Josu Martinez-Perdiguero

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Abstract

The origin of some mesophases of the ferroelectric nematic realm is not yet well understood. In this work we study the highly polar liquid crystal MIO, a close structural analogue of the prototypical ferroelectric nematogen DIO, which exhibits a ferroelectric smectic A to ferroelectric smectic C (SmAF-SmCF) phase transition. Calorimetric, dielectric and light-scattering experiments reveal that it is a second-order phase transition with mean-field behavior, and is driven by the softening of the tilt elastic constant accompanied by the divergence of the amplitude of the associated dielectric mode.

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Aitor Erkoreka, Mauricio Vera-Arévalo, Alberto Concellón, Sergio Diez-Berart, Jordi Sellarès, Adrià Gràcia-Condal, Ibon Alonso, Josu Martinez-Perdiguero. 2026-06-17. On the emergence of molecular tilt in a ferroelectric smectic liquid crystal with broken director-inversion symmetry. https://arxiv.org/abs/2606.18870

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