Abstract
Novel lactic acid derivatives containing an azo group in their molecular core have been synthesised and their mesomorphic properties established. Compounds with a short aliphatic non-chiral chain exhibited the SmA* phase and ferroelectric (FE) SmC* phase. The monotropic antiferroelectric (AF) phase was found in the homologues with a longer terminal chain. Spontaneous polarisation and tilt angle were measured for the FE and AF phases. Dielectric spectroscopy in the frequency range 1 Hz–10 MHz was carried out and dielectric properties established within the temperature range of the smectic phases. Two high frequency modes were detected in the AF phase. Small-angle X-ray measurements were conducted, and the temperature dependence of layer spacing values is established and discussed.
Acknowledgements
This work was supported by the German–Czech bilateral programme, DAAD No. D4–CZ5/ 2010–2011, between the German Academic Exchange Service and the Academy of Science of the Czech Republic (ASCR), by means of grants IAA100100911, 202/09/0047 and SVV–2010–261303.