Mesomorphic and Thermal Behavior of Symmetric Bent-Core Liquid Crystal Compounds Derived from Resorcinol and Isophthalic Acid

Catalina Ionica Ciobanu,Elena-Luiza Epure,Aurel Simion,Yahia Boussoualem,Irina Carlescu,Iulian Berladean,Gabriela Lisa

doi:10.3390/cryst11101215

Abstract

Bent-core liquid crystals (BCLC) have been widely studied as a result of their unusual polar and chiral properties. Similar to calamitic and discotic molecules, BCLC molecules also exhibit nematic phases, besides other higher order mesophases. The aim of this work is to comparatively analyze the mesomorphic behavior of some bent-core 1,3-disubstituted benzene core compounds derived from resorcinol and isophthalic acid. Thus, the two classes of compounds differ in the nature of the orientation of the ester bond between the benzene central core and the two branches attached to the core. The mesomorphic behavior was elucidated by polarized light optical microscopy and differential calorimetry. Given the relatively high isotropic points of the compounds, confirmation of the thermal stability in the domains manifesting liquid crystalline properties was performed by thermogravimetric studies. The theoretical explanation of the difference in mesomorphic behavior for the two classes was based on molecular modeling studies.

Highlights

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Bent-core molecules have attracted significant attention in the field of material science due to their remarkable and unique properties. This is because they exhibit macroscopic polar order and chirality in their mesophases, the constituent molecules are achiral [1,2,3,4,5,6,7]
The goal of this paper was to study the influence on the mesophase behavior of the The goal of this paper was to study the influence on the mesophase behavior of the ester unit orientation between the central benzene cycle and the two wings of ester unit orientation between the central benzene cycle and the two wings of symmetrically symmetrically bent‐core compounds derived from resorcinol and isophthalic acid, see bent-core compounds derived from resorcinol and isophthalic acid, see Figure 1

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Bent-core molecules have attracted significant attention in the field of material science due to their remarkable and unique properties. This is because they exhibit macroscopic polar order and chirality in their mesophases, the constituent molecules are achiral [1,2,3,4,5,6,7]. The initial application of these materials targeted the field of display application, at present researchers are looking to identify other uses, such as organic structural units for the fabrication of semiconductors or optical devices [8]

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