The first bent-core mesogens exhibiting a dimorphism B 7–SmCP A
2004; Royal Society of Chemistry; Volume: 14; Issue: 16 Linguagem: Inglês
10.1039/b316892a
ISSN1364-5501
AutoresG. Pelzl, Martin Schröder, Ulrike Dunemann, Siegmar Diele, W. Weißflog, Chris Jones, Dave Coleman, Noel A. Clark, Ralf Stannarius, Jianjun Li, Banani Das, Siegbert Grande,
Tópico(s)Synthesis and characterization of novel inorganic/organometallic compounds
ResumoNew homologous achiral five-ring bent-core mesogens with a lateral fluorine substituent at the central core and chlorine substituents at the terminal rings have been synthesized. Two mesophases could be distinguished by polarizing microscopy, calorimetry, X-ray, and electro-optical investigations. The high-temperature phase was found to be an antiferroelectric SmCP phase whereas the low-temperature phase could be identified as a ferroelectric B 7 phase. This phase sequence was observed for the first time. NMR measurements as well as optical studies indicate that both phases have a helical superstructure.
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