Novel liquid crystal trimers exhibiting a monolayer smectic C phase containing strong macroscopic fluctuations

Abstract

We prepared a homologous series of novel liquid crystal trimers, 1,4‐bis(4‐{ω‐[4‐(5‐dodecylpyrimidine‐2‐yl)phenyloxy]alkyloxyphenyl}carbonyloxy)benzene, I‐(m, n), and investigated their physical properties using optical microscopy, differential scanning calorimetry and X‐ray diffraction. All the compounds exhibited enantiotropic nematic (N) and smectic C (SmC) phases. Pronounced odd–even effects were apparent for the transition properties on varying the spacer length. X‐ray diffraction measurements suggest that the SmC phase has a monolayer structure in which the molecular long axis is tilted to the layer normal. Furthermore, formation of defect‐lines was observed for the SmC phases.

Acknowledgements

We thank Prof. Y. Maeda for X‐ray measurements of I‐(7, 7) and also thank Prof. J. Yamamoto for X‐ray measurements of I‐(9, 9). This work was partly supported by Aomori Prefecture Collaboration of Regional Entities for the Advancement of Technological Excellence, JST and a Grant for Priority Research Designated by the President of Hirosaki University.