Liquid-crystalline complexes of a lithium salt with twin oligomers containing oxyethylene spacers. An approach to anisotropic ion conduction

We have designed and synthesized liquid-crystalline twin oligomers containing oxyethylene chains as spacers as potential anisotropic ion conductors. These compounds have been complexed with lithium triflate. Although the single components of liquid-crystalline twin oligomers exhibit a nematic phase or directly melt into isotropic liquid, thermally stable smectic A phases have been induced by the incorporation of LiCF3SO3. The mesophase-isotropic transition temperatures increase with the increase of the concentration of the lithium salt. Ionic conductivities of the complexes have been measured in its monodomain of homeotropic alignment of the smectic A phase.