Unusual behaviour of binary mixtures of ferroelectric and antiferroelectric liquid crystals with three chiral centres

• Autorzy: Glogarova M. , Novotna V. , Kaspar M. , Hamplova V.
• Języki publikacji: EN

Abstrakty

EN

Two binary mixtures have been studied of homologues from a series derived from 4-alkoxybiphenyl-4'-carboxylic acid with three chiral centres exhibiting ferroelectric (FE), antiferroelectric (AF) and tilted hexatic phases. One homologue exhibits a re-entrant SmC* (SmC*_re) phase, which is miscible with the SmC* phase. The phase diagrams of the studied mixtures exhibit a close pocket of the SmC*_A phase. The SmC*_re phase is induced even in the mixtures composed of homologues without this phase. Dielectric spectroscopy reveals the Goldstone mode in both ferroelectric SmC* and the SmC*_re phases, this mode being stroger when increasing concentration of the antiferroelectric homologue. In the SmC*_A phase a relaxation mode is detected with the relaxation frequency three orders higher, which exhibits critical slowing down when approaching the SmC*_re phase. This mode, which can be attributed to the anti - phase mode, is responsible for the apperance of SmC*_re phase. In mixtures exhibiting the SmC*_A phase a helix twist inversion occurs in the vinicity of the low temperature border of the AF phase.

Słowa kluczowe

EN

binary mixture; ferroelectric phase; antiferroelectric phase; re-entrant ferroelectric phase; dielectric spectroscopy; soft anti-phase mode

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2002
• Tom: Vol. 10, No. 1
• Strony: 47--52
• Opis fizyczny: Bibliogr. 12 poz.

Twórcy

autor

Glogarova M.

• Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague 8, Czech Republic

autor

Novotna V.

• Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague 8, Czech Republic

autor

Kaspar M.

• Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague 8, Czech Republic

autor

Hamplova V.

• Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague 8, Czech Republic

Bibliografia

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