J. Phys. France
Volume 51, Numéro 16, août 1990
Page(s) 1749 - 1757
J. Phys. France 51, 1749-1757 (1990)
DOI: 10.1051/jphys:0199000510160174900

Electro-optical and thermal studies of one ferroelectric liquid-crystal compound with a polarization sign reversal

C.C. Huang1, T. Min1, D.S. Lin1, B. Zhou1 et J.W. Goodby2

1  School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, U.S.A.
2  School of Chemistry, The University, Hull HU6 7RX, G.B.

Temperature variations of heat capacity, optical tilt angle, polarization, and helical pitch have been measured in the vicinity of the smectic-A (SmA)-chiral-smectic-C (SmC*) transition of one liquid-crystal compound which exhibits an unusual reversal behavior in polarization at about 25 °C while the SmA-SmC* transition occurs at 50 °C. Unexpectedly, from our detailed calorimetric and optical microscopy studies, we have found that the recrystallization also occurs around 25 °C during a reasonably slow cooling experimental run.

7820J - Electrooptical effects.
7722 - Dielectric properties of solids and liquids.
6520 - Thermal properties of liquids: heat capacity, thermal expansion, etc..
6470M - Transitions in liquid crystals.

Key words
dielectric polarisation -- dielectric properties of liquids and solutions -- electro optical effects -- ferroelectric liquid crystals -- liquid crystal phase transformations -- molecular orientation -- optical microscopy -- recrystallisation -- smectic liquid crystals -- specific heat of liquids