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  • Open Access

Landau-de Gennes modeling of confinement effects and cybotactic clusters in bent-core nematic liquid crystals

Yucen Han

Prabakaran Rajamanickam

Bedour Alturki

Apala Majumdar*

  • *Contact author: apala.majumdar@manchester.ac.uk
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Phys. Rev. E 113, 025403 – Published 2 February, 2026

DOI: https://doi.org/10.1103/w85s-mwn3

Abstract

We study bent-core nematic (BCN) systems in two-dimensional (2D) and three-dimensional (3D) settings, focusing on the role of cybotactic clusters, phase transitions, confinement effects, and applied external fields. We propose a generalized version of Madhusudana's two-state model for BCNs [Phys. Rev. E 96, 022710 (2017)] with two order parameters: Qg to describe the ambient ground-state (GS) molecules and Qc to describe the additional ordering induced by the cybotactic clusters. The equilibria are modeled by minimizers of an appropriately defined free energy, with an empirical coupling term between Qg and Qc. We demonstrate two phase transitions in spatially homogeneous 3D BCN systems at fixed temperatures: a first-order nematic-paranematic transition followed by a paranematic-isotropic phase transition driven by the GS-cluster coupling. We also numerically compute and give heuristic insights into solution landscapes of confined BCN systems on 2D square domains, tailored by the GS-cluster coupling, temperature, and external fields. This benchmark example illustrates the potential of this generalized model to capture tunable director profiles, cluster properties, and potential biaxiality induced by antagonistic Qg and Qc profiles.

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Phys. Rev. E 113, 025403– Published 2 February, 2026
  • Received 23 August 2025
  • Accepted 6 January 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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