Anomalous phase sequence in new chiral liquid crystalline materials

Abstract

We have prepared and studied a series of rod-like liquid crystalline compounds with the molecular core laterally substituted by bromine atom and with the lactate unit in the chiral terminal chain. Microscopic observation under the polarising microscope, x-ray and dielectric spectroscopy results enable us to establish the TGBA–SmA–TGBA_RE–TGBC phase sequence. The presence of the re-entrant TGBA phase below the regular SmA phase, found for three homologues, is quite uncommon. Results are discussed and compared with the previously studied compounds with regular phase sequences.

Keywords:

• chiral chain
• lactate unit
• TGBA phase
• re-entrancy
• TGBC phase

Funding

This work was supported by Grant Agency of the Czech Republic [grant number P204/11/0723], [grant number CSF 13-14133S] and project M100101211 from ASCR.