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Rational Design of Rod-Like Liquid Crystals Exhibiting Two Nematic Phases.

ABSTRACT: Recently, a polar, rod-like liquid-crystalline material was reported to exhibit two distinct nematic mesophases (termed N and N_X ) separated by a weakly first-order transition. Herein, we present our initial studies into the structure-property relationships that underpin the occurrence of the lower-temperature nematic phase, and report several new materials that exhibit this same transformation. We have prepared material with significantly enhanced temperature ranges, allowing us to perform a detailed study of both the upper- and lower-temperature nematic phases by using small-angle X-ray scattering. We observed a continuous change in d spacing rather than a sharp change at the phase transition, a result consistent with a transition between two nematic phases, structures of which are presumably degenerate.

SUBMITTER: Mandle RJ

PROVIDER: S-EPMC5656819 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Rational Design of Rod-Like Liquid Crystals Exhibiting Two Nematic Phases.

Mandle Richard J RJ Cowling Stephen J SJ Goodby John W JW

Chemistry (Weinheim an der Bergstrasse, Germany) 20170918 58

Recently, a polar, rod-like liquid-crystalline material was reported to exhibit two distinct nematic mesophases (termed N and N<sub>X</sub> ) separated by a weakly first-order transition. Herein, we present our initial studies into the structure-property relationships that underpin the occurrence of the lower-temperature nematic phase, and report several new materials that exhibit this same transformation. We have prepared material with significantly enhanced temperature ranges, allowing us to p ...[more]

PMID: 28850751

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