Dataset Information

Polar Switching and Cybotactic Nematic Ordering in 1,3,4-Thiadiazole-Based Short-Core Hockey Stick-Shaped Fluorescent Liquid Crystals.

ABSTRACT: We report here the synthesis and thermotropic properties of novel short-core hockey stick-shaped liquid crystalline molecules based on the 1,3,4-thiadiazole core. Polar switching behavior is observed in the cybotactic nematic and smectic mesophases for the bent-core thiadiazole derivatives. The presence of the lateral methoxy moiety in the outer phenyl ring of the four-ring molecules facilitates the formation of spontaneous ordering in the nematic phase observed via X-ray diffraction measurements. Anomalous temperature dependence of spontaneous polarization on cooling is explained by the possible antiferroelectric packing of the molecules that require higher electric field for switching. The compounds exhibited a strong absorption band at ?356 nm and a blue emission band at ?445 nm with a good quantum yield of ?_f ?0.39. The mega Stokes shift is observed and depends on the nature of the solvent.

SUBMITTER: Saha SK

PROVIDER: S-EPMC6648508 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Publications

Polar Switching and Cybotactic Nematic Ordering in 1,3,4-Thiadiazole-Based Short-Core Hockey Stick-Shaped Fluorescent Liquid Crystals.

Saha Sandip Kumar SK Mohiuddin Golam G Paul Manoj Kumar MK Gupta Santosh Prasad SP Khan Raj Kumar RK Ghosh Sharmistha S Pal Santanu Kumar SK

ACS omega 20190426 4

We report here the synthesis and thermotropic properties of novel short-core hockey stick-shaped liquid crystalline molecules based on the 1,3,4-thiadiazole core. Polar switching behavior is observed in the cybotactic nematic and smectic mesophases for the bent-core thiadiazole derivatives. The presence of the lateral methoxy moiety in the outer phenyl ring of the four-ring molecules facilitates the formation of spontaneous ordering in the nematic phase observed via X-ray diffraction measurement ...[more]

PMID: 31459861

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Dataset Information

Polar Switching and Cybotactic Nematic Ordering in 1,3,4-Thiadiazole-Based Short-Core Hockey Stick-Shaped Fluorescent Liquid Crystals.

Publications

Polar Switching and Cybotactic Nematic Ordering in 1,3,4-Thiadiazole-Based Short-Core Hockey Stick-Shaped Fluorescent Liquid Crystals.

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