Fluorescence microscopy reveals molecular localisation at line defects in nematic liquid crystals

Takuya Ohzono, Kaoru Katoh, Jun Ichi Fukuda

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

Topological defects easily form in liquid crystals (LCs) as a result of frustrations in spatially dependent anisotropic molecular ordering, and have been regarded as promising tools for facilitating manipulation of relatively large non-LC materials such as colloids. However, it remains unclear whether low-molecular-weight (LMW) impurities that do not aggregate or self-assemble in bulk LCs because of the dominance of entropy can localise at LC defects. Here, by fluorescence microscopy, we directly show the localisation of LMW molecules at the topological line defects of a nematic LC. It is theoretically explained that excess free energy density of nematic ordering at the defect core allows LMW solutes to accumulate at a non-negligible level overcoming the entropy leading to their uniform distributions. Our results demonstrate the usefulness of LC defects as a bottom-up field that enables micromanipulation of LMW molecules and realisation of transformable three-dimensional micro-architectures composed of versatile small functional molecules.

Original languageEnglish
Article number36477
JournalScientific reports
Volume6
DOIs
Publication statusPublished - Nov 4 2016
Externally publishedYes

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low molecular weights
liquid crystals
microscopy
fluorescence
defects
crystal defects
entropy
molecules
frustration
colloids
manipulators
solutes
flux density
free energy
impurities
crystals

All Science Journal Classification (ASJC) codes

  • General

Cite this

Fluorescence microscopy reveals molecular localisation at line defects in nematic liquid crystals. / Ohzono, Takuya; Katoh, Kaoru; Fukuda, Jun Ichi.

In: Scientific reports, Vol. 6, 36477, 04.11.2016.

Research output: Contribution to journalArticle

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