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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Electrical conductivity studies on discotic liquid crystal-ferrocenium donor-acceptor systems.
P Suresh Kumar1, Sandeep Kumar, V Lakshminarayanan
1Raman Research Institute, CV Raman Avenue, Sadashivanagar, Bangalore 560 080, India.
The Journal of Physical Chemistry. B
|April 1, 2008
Summary
Electron-deficient ferrocenium ions were dispersed in electron-rich liquid crystals, forming donor-acceptor systems. This enhanced conductivity in the discotic system without changing its structure.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Supramolecular Chemistry
Background:
- Triphenylene-based discotic liquid crystals exhibit columnar hexagonal mesophases.
- Electron-rich discotic molecules can form charge-transfer complexes.
- Controlling conductivity in liquid crystalline materials is of significant interest.
Purpose of the Study:
- To investigate the dispersion of electron-deficient ferrocenium ions within electron-rich triphenylene-based columnar hexagonal liquid crystals.
- To characterize the resulting composites and their electronic properties.
- To understand the impact of ferrocenium ion incorporation on the liquid crystalline mesophase and conductivity.
Main Methods:
- Polarizing optical micrography (POM) for mesophase characterization.
- Differential scanning calorimetry (DSC) for thermal analysis.
- Small-angle X-ray scattering (SAXS) for structural analysis.
- Visible absorption spectroscopy for charge-transfer complex formation.
- DC and AC conductivity measurements for electronic transport properties.
Main Results:
- Successful dispersion of ferrocenium ions in triphenylene-based liquid crystals.
- Formation of donor-acceptor systems and charge-transfer complexes confirmed by spectroscopy.
- Enhanced quasi-one-dimensional conductivity of the discotic system.
- Preservation of the hexagonal columnar mesophase structure.
Conclusions:
- Ferrocenium ion incorporation creates effective donor-acceptor systems within discotic liquid crystals.
- The charge-transfer interaction significantly enhances the quasi-one-dimensional conductivity.
- The hexagonal columnar liquid crystalline structure remains stable upon ion doping.
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