Proceedings Article | 27 August 2008
KEYWORDS: Silicon, Liquid crystals, Chromium, Crystals, Liquids, Photomicroscopy, Liquid crystal on silicon, Silicon carbide, X-rays, Thermography
We found that 1-alkyl-4-phenyl-2,2,3,3,5,5,6,6,7,7,8,8-dodecamethyl-2,3,5,6,7,8-hexasilabicyclo[2.2.2]octanes exhibited
hexagonal columnar phases with an alkyl group ranging from a methyl to a pentyl group. Introduction of a cyano group
at para-position of the phenyl group was found to enhance the stability of the columnar phases. The observed columnar
phases strikingly contrasted with a nematic phase of 1-alkyl-4-(4-cyanophenyl)bicyclo[2.2.2]octanes. Furthermore, the
polysilacage derivatives with such short alkyl groups as n-propyl, n-butyl, n-pentyl, and n-hexyl at 1-position, that
contain neither long alkyl groups nor aromatic rings, were also disclosed to exhibit columnar mesophases, indicating that
the polysilacage moiety has a high tendency to form columnar structure.
