Phase Transitions and Switching Behavior in a Fluorine-Containing Ferroelectric Liquid Crystal

Abstract

Phase transitions and switching behavior in a fluorine containing ferroelectric liquid crystal, whose optical purity was controlled by mixing (R) and (S) enantiomorphs, were studied. Only for the pure (R) or (S) enantiomorphs, the phase transition from the SmA to the third state SmCA *, occurred directly. For the mixtures of (R) and (S) enantiomorphs, the phase transition occurred from the SmA to the SmCA * via the SmC*. In these mixtures, with decreasing temperature in SmC*, internal disclination loops changed from “boat type” to “stripe type”.

Current Topics in Smectic Liquid Crystal Research

“…Often the synclinic SmC phase is induced even if it is not present in the optically pure sample. [145,149] An extreme example is the compound MHPBC, which in its optically pure form exhibits all chiral SmC-type variants except the ordinary SmC* phase, whereas this phase is the only variant present if the optical purity is lowered below 50 % enantiomeric excess. [150] The SmC a *, SmC b *, and SmC g * phases are often collectively referred to as "subphases".…”

Synthesis and physical properties of difluoroterphenyl ferroelectric liquid crystal with mixed alkenyloxy‐ester terminal ends

“…The work presented in this paper consists of the design, synthesis and characterization of the ferroelectric liquid crystal S(+)-(2-octyl)-40-decenyloxy-3,39-difluoroterphenyl-4-carboxylate (see structure in figure 1; designated as compound 11), with improved electro-optical properties suitable for display applications [5,6]. Electro-optic results will be presented elsewhere.…”

Multistable antiferroelectric liquid-crystal optical modulator

“…4͒. In MHPOBC-PSCOF, the propagating waves 10,11 are associated with the slowest mode. This leads us to believe that the field induced stripe defects 10 must be responsible for the memory effect.…”

“…For example, the switching can occur without propagating waves. 10,11 Furthermore, they are multistable as they retain the level of optical transmission for several hours after the switching pulse has been turned off.…”