2015/06/08 by Raffaele Tavarone, Patrick Charbonneau, Holger Stark · 2 citations
Materials Science · Mathematics · Physics and Astronomy · #Bent molecular geometry #Condensed matter physics #Disclination #Isotropy #Liquid Crystal Research Advancements #Liquid crystal #Material Dynamics and Properties #Materials science #Mathematics #Monte Carlo method #Optics #Phase (matter) #Phase diagram #Phase transition #Physics #Quantum mechanics #Theoretical and Computational Physics #cond-mat.stat-mech
paper · pdf · doi:10.1063/1.4930886
published as J. Chem. Phys. 143, 114505 (2015) · 14 pages, 12 figures
arxiv created 2015/06/08 · openalex publication_date 2015/09/16 · arxiv updated 2016/04/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We perform extensive Monte Carlo simulations of a two-dimensional bent hard-needle model in both its chiral zig-zag and its achiral bow-shape configurations and present their phase diagrams. We find evidence for a variety of stable phases: isotropic, quasi-nematic, smectic-C, anti-ferromorphic smectic-A, and modulated-nematic. This last phase consists of layers formed by supramolecular arches. They create a modulation of the molecular polarity whose period is sensitively controlled by molecular geometry. We identify transition densities using correlation functions together with appropriately defined order parameters and compare them with predictions from Onsager theory. The contribution of the molecular excluded area to deviations from Onsager theory and simple liquid crystal phase morphology is discussed. We demonstrate the isotropic-quasi-nematic transition to be consistent with a Kosterlitz-Thouless disclination unbinding scenario.