Thermal hysteresis at the phase transition in liquid crystalline materials

Experimental results on antiferroelectric liquid crystalline materials are presented using techniques such as dielectric and electro-optical measurements. A demixing phenomenon has been observed for compounds exhibiting the ferroelectric SmC* phase in their phase sequence. This phenomenon is interpreted within the framework of a thermodynamic study. Large temperature hysteresis during cooling and heating has been observed and is discussed. The results of dielectric spectroscopy and electro-optical properties suggest that thermal hysteresis is related to the demixing phenomenon. The effect of cell thickness and spontaneous polarisation on the temperature range of this phenomenon has also been investigated.

[1]  M. Hird.  Ferroelectricity in liquid crystals—materials, properties and applications , 2011 .

[2]  D. Pociecha,et al.  Reentrant orthogonal smectic-A phase below a tilted smectic-C phase in a chiral compound. , 2011, Physical review. E, Statistical, nonlinear, and soft matter physics.

[3]  U. Manna,et al.  X-ray diffraction study of ferroelectric and antiferroelectric liquid crystal mixtures exhibiting de Vries SmA∗-SmC∗ transitions. , 2010, Physical review. E, Statistical, nonlinear, and soft matter physics.

[4]  H. Nguyen,et al.  Synthesis, characterisation and behaviour under a field of a chiral smectic liquid crystal , 2009 .

[5]  H. Dhaouadi,et al.  Electric field-induced phase transitions in a smectic chiral liquid crystal , 2009 .

[6]  J. K. Vij,et al.  Effect of cell surfaces on the stability of chiral smectic-C phases. , 2008, Physical review. E, Statistical, nonlinear, and soft matter physics.

[7]  H. Nguyen,et al.  Field-temperature phase diagrams in chiral tilted smectics, evidencing ferroelectric and ferrielectric phases , 2007, The European physical journal. E, Soft matter.

[8]  V. Manjuladevi,et al.  Electric field‐induced birefringence, optical rotatory power and conoscopic measurements of a chiral antiferroelectric smectic liquid crystal , 2007 .

[9]  M. Hamaneh,et al.  Range of interlayer interactions in smectic- C liquid crystals. , 2007, Physical review. E, Statistical, nonlinear, and soft matter physics.

[10]  F. Nallet,et al.  Extension of the resonant scattering technique to liquid crystals without resonant element , 2006, The European physical journal. E, Soft matter.

[11]  H. Orihara,et al.  Electric-field-temperature phase diagram of an antiferroelectric liquid crystal. , 2005, Physical review. E, Statistical, nonlinear, and soft matter physics.

[12]  G. Joly,et al.  Correlation between dielectric and optical measurements in the smectic-C(*)(alpha) phase. , 2004, Physical review. E, Statistical, nonlinear, and soft matter physics.

[13]  S. K. Kundu,et al.  Dielectric relaxation behavior of a liquid crystal showing an unusual type of antiferroelectric-ferroelectric-antiferroelectric phase sequence. , 2003, Physical review. E, Statistical, nonlinear, and soft matter physics.

[14]  R. Dabrowski,et al.  Enantiomeric excess dependence of the phase diagram of antiferroelectric liquid crystals. , 2002, Physical review. E, Statistical, nonlinear, and soft matter physics.

[15]  G Srajer,et al.  Interlayer structures of the chiral smectic liquid crystal phases revealed by resonant X-ray scattering. , 2002, Physical review. E, Statistical, nonlinear, and soft matter physics.

[16]  S. Lagerwall,et al.  Surface- and Field-Induced AFLC Structures Detected by Dielectric Spectroscopy , 2002 .

[17]  H. Nguyen,et al.  Anomalous thermal hysteresis in the SmC* phase of 10FHBBBM7*, revealed by dielectric measurements , 2001 .

[18]  M. Glogarová,et al.  Re-entrant ferroelectric phases in binary mixtures of ferroelectric and antiferroelectric homologues of a series with three chiral centers , 2001 .

[19]  R. Blinc,et al.  Electro-optic response of an antiferroelectric liquid crystal in submicron cells , 2001 .

[20]  J. Mieczkowski,et al.  Reentrant ferroelectricity in liquid crystals. , 2000, Physical review letters.

[21]  V. F. Petrov,et al.  X-ray diffraction study of some liquid crystalline 2,5-disubstituted 1, 3, 2-dioxaborinane derivatives , 2000 .

[22]  T. Qian,et al.  Field-induced phase transitions in antiferroelectric liquid crystals. , 1999, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[23]  J. Parneix,et al.  Relaxation processes in the ferrielectric and alpha phases of antiferroelectric liquid crystals , 1998 .

[24]  S. Lagerwall,et al.  Collective and non-collective excitations in antiferroelectric and ferrielectric liquid crystals studied by dielectric relaxation spectroscopy and electro-optic measurements , 1997 .

[25]  González,et al.  Broadband dielectric measurements on the (R)-1-methylheptyl-6-(4'-decyloxybenzoyloxy)-2-naphthalene carboxylate antiferroelectric liquid crystal. , 1996, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[26]  M. Glogarová,et al.  Ferroelectric and antiferroelectric modes in a new chiral thiobenzoate liquid crystal , 1996 .

[27]  J. Goodby,et al.  An investigation of the field-induced ferrielectric subphases in antiferroelectric liquid crystals , 1995 .

[28]  P. Cluzeau,et al.  New chiral thiobenzoate series with antiferroelectric mesophases , 1994 .

[29]  Y. Takanishi,et al.  Antiferroelectric chiral smectic liquid crystals , 1994 .

[30]  A. Fukuda,et al.  Dielectric relaxation modes in the antiferroelectric smectic CA* phase , 1993 .

[31]  J. Hatano,et al.  Field-Induced Phase Transitions in Antiferroelectric Liquid Crystal , 1993 .

[32]  H. Orihara,et al.  A Phenomenological Theory of the Antiferroelectric Phase Transition in Smectic Liquid Crystals , 1990 .

[33]  C. Tschierske,et al.  Synthesis and Mesomorphic Properties of Axially Cyano-Substituted 1,3-Dioxane-5-Carboxylates , 1989 .

[34]  G. Pelzl,et al.  New Binary Liquid Crystal Systems with the Phase Sequence SA SC SA , 1989 .