Julita S. Gasowska
The influence of an alkenyl terminal group on the mesomorphic behaviour and electro-optic properties of fluorinated terphenyl liquid crystals
Gasowska, Julita S.; Cowling, Stephen J.; Cockett, Martin C. R.; Hird, Michael; Lewis, Robert A.; Raynes, E. Peter; Goodby, John W.
Stephen J. Cowling
Martin C. R. Cockett
Dr Mike Hird M.Hird@hull.ac.uk
Reader in Organic Chemistry/ Admissions Tutor/ Director of Chemistry Part-Time Blended Learning and Apprenticeship Programmes.
Robert A. Lewis R.A.Lewis@hull.ac.uk
E. Peter Raynes
John W. Goodby
Novel liquid crystal terphenyls with two, three and four lateral fluoro substituents and an alkene unit at the end of a terminal chain are presented in terms of synthesis, mesomorphic behaviour and electro-optic properties. The difluoro analogues were found to exhibit the smectic C phase over a wide temperature range, with short temperature ranges of the smectic A and the nematic phase above. Very low melting points were recorded for the trifluoro analogues, and the shorter chain homologues of these materials exhibit the nematic phase over a wide temperatures with a monotropic smectic C phase and the higher homologues exhibit the smectic C phase over a wide temperature range with the nematic phase above. The tetrafluoroterphenyls exhibit the nematic phase over a wide temperature range with the complete absence of smectic phases. As appropriate, the materials were evaluated for dielectric anisotropy and threshold voltage in nematic phase, and mixed with a chiral dopant to evaluate the spontaneous polarisation, tilt angle and switching times in the chiral smectic C phase. The results show that these compounds are strong potential candidates for application in both vertically aligned nematic (VAN) and ferroelectric liquid crystal (FLC) devices.
|Journal Article Type||Article|
|Publication Date||Jan 1, 2010|
|Journal||JOURNAL OF MATERIALS CHEMISTRY|
|Publisher||Royal Society of Chemistry|
|Peer Reviewed||Peer Reviewed|
|APA6 Citation||Gasowska, J. S., Cowling, S. J., Cockett, M. C. R., Hird, M., Lewis, R. A., Raynes, E. P., & Goodby, J. W. (2010). The influence of an alkenyl terminal group on the mesomorphic behaviour and electro-optic properties of fluorinated terphenyl liquid crystals. Journal of materials chemistry, 20(2), 299-307. doi:10.1039/b914260f|
|Keywords||Materials Chemistry; General Chemistry|
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