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Four racemic compounds (R, S)-4′-(1-methylheptyloxycarbonyl)biphenyl-4-yl 4-[3-(2,2,3,3,4,4,4-heptafluorobutoxy)prop-1-oxy]benzoates were synthesized and characterized. Their mesomorphic properties, such as phase transitions temperatures and enthalpies were measured by polarizing optical microscope and differential scanning calorimetry. The example of mixture containing racemic components and its properties is presented.

New antiferroelectric fluorinated mixture W-1000 was made. Typical two dielectric modes with frequencies around 1–10 kHz and 100 kHz–1 MHz were detected in . Additionally high frequency mode was observed with relaxation frequency higher than 1 MHz. All modes in antiferroelectric phase were discussed.

Orthoconic Antiferroelectric Liq. Cryst. (OAFLC) have been extensively studied due to their unique electrooptical properties [1,2]. Practical implementation of this kind of liquid crystalline medium experiences many obstacles including a number of parasitic effects deteriorating the electrooptical performance. In search for working OAFLC a mixture with the helical pitch longer than the typical cell gap was formulated. Using this mixture near perfect optical uniformity and excellent dark state at the zero electric field applied was obtained. The physical and structural properties of mixture are presented and their parameters are discussed. The electrooptical performance is presented and discussed.

Chiral liquid crystal phases have been attracting great interest in the past years because of their unique optical properties, such as: selective light reflection, optical dichroizm, ferro- and antiferroelectric behavior. One of the most popular ways of obtaining such materials is an addition of chiral dopants with high helical twisting power to the achiral liquid crystal mixtures. The aim of this paper is to investigate the dependence of helical twisting power on the spacer length and fluorosubstitution in recently prepared chiral three-ring esters with perfluorinated alkanoyloxy unit in a terminal chain.

W-1000 orthoconic antiferroelectric liquid crystal eutectic mixture was prepared in Military University of Technology. This mixture is probably the broadest antiferroelectric mixture, ever prepared. Precise dielectric measurements were performed in a broad temperature range. Some parameters of detected modes and their temperature characteristics are found. It seems that in different temperature regions of orthoconic antiferroelectric liquid crystal different numbers of modes should be anticipated to fit experimental results. Results are discussed with respect to the theoretical model.

Three new antiferroelectric mixtures W-1000, W-1000A and W-1000B and their components W-1, W-2 and B-3 synthesized at Military University of Technology were investigated by dielectric spectroscopy. Typical relaxation modes in smectic phases and one mode in isotropic phase never observed before were detected. Obtained results were discussed in terms of composition of investigated mixtures and molecular structures of their components.

In search of the long pitch, orthoconic antiferroelectric liquid crystalline mixture (OAFLC), the high tilted host mixture with antiferroelectric smectic phase (AFLC) was formulated. The influence of the molecular dipole moment magnitude and orientation on physical properties of the AFLC was tested by doping of the host by three different dopants. The extensive study of the host material and obtained admixtures was done. Results are discussed in the context of the influence of the molecular dipole moment orientation and magnitude of the dopant on the tilt, helical pitch and spontaneous polarization of the phase of obtained mixtures.

Phase transitions temperatures and temperature dependence of helical pitch p for S-(+)-4′-(1-methylheptyloxycarbonyl)biphenyl-4-yl 4-[(4,4,4,3,3,2,2-heptafluorobutoxy)alkoxy] benzoates, and 3-fluoro-, and 2-fluoro-, 2,3-difluoro-benzoates upon length of alkoxy spacer were tested. For etoxy and propoxy spacer the pitch p in antiferroelectric phase is increasing with temperature to maximal value of about 1000 nm in high temperatures region. For pentoxy, hexoxy, and heptoxy spacer the pitch p is longer and reverse temperature dependence is observed. The compounds convenient for formulation of antiferroelectric orthoconic mixture with pitch length of about 2000 nm were selected.

Three different Antiferroelectric Liquid Crystals, synthesized in Military University of Technology were investigated by dielectric means. Some of them are orthoconic. The structures of studied compounds are very similar. The only one difference is presented in rigid core. The position and number of Fluorine atoms in rigid core changes. Very rich dielectric modes are detected with frequencies from 50 Hz up to 40 MHz. In this paper, dielectric spectroscopy of investigated materials is presented.

Two structurally similar homologous series of chiral esters with partially fluorinated alkoxyalkoxy terminal chains are described. Their synthetic routes and mesomorphic properties, such as phase transitions temperatures and enthalpies, are characterized by polarizing optical microscope and differential scanning calorimetry.