Banana‐shaped dopants for flexoelectric nematic mixtures

Abstract

The synthesis is reported of new meta‐substituted quaterphenyls and several related dimers as dopants for nematic mixtures with flexoelectric properties. The number and nature of the terminal substituents is varied from apolar with a small dipole moment to polar with a strong dipole moment. The number of methylene units in the flexible aliphatic spacer between the polyfluorinated aromatic groups of the dimers is also varied. Dimers capable of banana‐shaped conformers induce an increase in the flexoelectric coefficients of mixtures containing them and reduce the clearing point to a small extent.

Keywords:

• banana‐shaped dopant
• flexoelectric nematic
• quarterphenyl
• dimer

Acknowledgements

We express our thanks to the Merck Chemicals Ltd for funding a PhD studentship (NA). We would also like to thank B. Worthington (¹H NMR) and K. Welham (MS) for spectroscopic measurements.