An Influence of a Single Fluorine Atom Position in the Molecular Rigid Core on Physical Properties of Orthoconic Antiferroelectric Liquid Crystal

Abstract

The homologous series of mesogenic (S)-4″[n-(perfluoroalkanoyloxy)hexyl-1-oxy]-4-(1-metylheptyloxy-carbonyl)terphenyl compounds exhibiting low temperature, wide range, near orthoconic antiferroelectric phase has been synthesized [1]. Compounds of the homologous series differ from each other by a position of a single fluorine atom substituted at the phenyl ring of the molecular rigid core. This affects the mesogenic behavior. Moreover, the molecular dipole moment of the compound as well as the physical parameters of the antiferroelectric phase are changed. The importance of the molecular dipole moment orientation and magnitude for the mesogenic behavior and physical parameters of the orthoconic antiferroelectric phase is discussed.

Keywords:

• fluoro substitution
• smectic liquid crystals
• tilt angle
• orthoconic smectic phases

Acknowledgments

We would like to express our gratitude to Prof. E. Górecka and dr. D. Pociecha for X-ray measurements and fruitful discussion.

This work was done under KBN grant for Polish-Singapore cooperation no.: Singapore/13/2006 (Grant WAT SPG 29041/WAT/2006).