Dipolar phases in liquid crystals with the chiral part based on the lactic acid

Abstract

New lactic acid derivatives exhibit paraelectric SmA and TGBA phases, ferroelectric SmC* and TGBC phases and antiferroelectric phases, the TGB and antiferroelectric phases being unusually broad. The polymorphism depends on the number of lactate units in the chiral chain and on the length of the non-chiral chain. The dielectric spectroscopy revealed the characteristic modes in all these phases. In phases with the dipolar order the spontaneous polarization and the tilt angle have been determined.

Keywords:

• liquid crystals
• paraelectric, ferroelectric and antiferroelectric phases
• TGB phases
• lactate unit

Acknowledgement

This work was supported by Projects No. IAA100100710 from Grant Agency of the Academy of Sciences of the Czech Republic, Project Czech-Polish bilateral collaboration program No. 8 (2006-2007) and OC 175 program under the Ministry of Education, Youth and Sports of the Czech Republic.