Novel fluorinated ferroelectric organosiloxane liquid crystals

A progress report on the synthesis and characterisation of a series of fluorinated chiral bi-mesogen low molar mass organosiloxane materials is presented. The mesogenic moiety is identical to that in the TSiKN65F mono-mesogen material reported by Naciri et al., which displays a de Vries-type SmA* phase. The parameter varied across the series is the length of the alkyl chain linking the mesogen moiety to the siloxane. The material with 10 carbon atoms in the chains displays a stable smectic phase with ferroelectric response at room temperature, whereas the materials with 6, 7 and 8 carbon atoms tend to crystallize.