Orientation and solvatochromism of dyes in liquid crystals

Palsson, L-O.; Szablewski, M.; Roberts, A.; Masutani, A.; Love, G.D.; Cross, G.H.; Bloor, D.; Kay, A.J.; Woolhouse, A.D.; Yasuda, A.

Abstract

The orientation and solvatochromism of some dye molecules in a liquid crystal have been investigated. Interactions with the host and the structure of the dye molecule affect the macroscopic alignment of dichroic dye molecules in a liquid crystal: It was observed that some dye molecules show a large bathochromic shift of their absorption maxima in the liquid crystal host relative to the situation in isotropic solvents. It is suggested that this is due to the occurrence of a much weaker reaction field in the anisotropic, rigid host. These dye molecules show little or no apparent order in the anisotropic host despite the observation of a reduction in the electro optic switching time when the dye is present. The highest degree of macroscopic alignment was observed for a merocyanine compound, which showed the smallest solvatochromic shift in the liquid crystal host. These results are discussed in terms of the steric, dipolar and hydrogen bond interactions between the guest and the host.

Citation

Palsson, L., Szablewski, M., Roberts, A., Masutani, A., Love, G., Cross, G., …Yasuda, A. (2003). Orientation and solvatochromism of dyes in liquid crystals. Molecular Crystals and Liquid Crystals, 402(1), 43-53. https://doi.org/10.1080/744816685

• Journal Article Type: Article
• Publication Date: Jan 1, 2003
• Deposit Date: Dec 19, 2006
• Publicly Available Date: Nov 18, 2014
• Journal: Molecular Crystals and Liquid Crystals
• Print ISSN: 1542-1406
• Electronic ISSN: 1563-5287
• Publisher: Taylor and Francis Group
• Peer Reviewed: Peer Reviewed
• Volume: 402
• Issue: 1
• Pages: 43-53
• DOI: https://doi.org/10.1080/744816685
• Keywords: Anisotropy, Guest-host interactions, Orientation, Order parameter, Solubility.
• Public URL: https://durham-repository.worktribe.com/output/1581890