Pressure-temperature-volume (pVT) measurements were carried out on 2-(4-hexyloxyphenyl)-5-octyl-pyrimidine, a substance exhibiting nematic and smectic A and C polymorphism. Analysis of the longitudinal relaxation times obtained recently for elevated pressures [Czub et al., Z. Naturforsch. A: Phys. Sci. 58, 333 (2003)] was performed for isobaric, isothermal, and isochoric conditions within the two smectic phases. Several relationships linking the dynamical and thermodynamical quantities, derived recently for isotropic glass formers [Roland et al. Rep. Prog. Phys. 68, 1405 (2005)], were found to hold for the liquid crystal, revealing a striking similarity of behaviors for these two types of materials. The parameter gamma characterizing the steepness of the interaction potential was derived in different ways. It is interesting that the liquid crystal gives relaxation time versus TV(-gamma) plots that are linear, unlike results for glass formers, implying that the dynamics of the former is thermally activated.

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The phenomenon of an induction of the chiral anticlinic phase is described. The ability for induction of the antiferroelectric phase of compounds with cyano and fluorinated groups in terminal positions is tested by the comparison of phase diagrams of their mixtures. The results of DSC, electrooptic and X-ray measurements for two systems are presented. The induction of the antiferroelectric phase is confirmed by extensive physical studies.

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The results of helical pitch measurements for the systems, in which induced antiferroelectric phase is observed, are presented. The bicomponent systems composed of the chiral three ring ester with partially fluorinated terminal alkyl chain 4- 2H-perfluorooctyloxy)biphenylate-4 and a member of homologous series of chiral three ring ester with protonated chain -4-(1-methylheptyloxycarbonyl)biphenyl-4 -yl 4-(3-alkanoyloxyprop-1-oxy)benzoates were investigated. The influence of alkyl chain length and the concentration of the hydrogenous component on the induction and helical pitch are discussed. The increase of concentration of a component with the alkyl chain causes the increase of helical pitch inferro and antiferroelectric phase. The increase of alkyl chain length causes the lengthening of helical pitch in ferroelectric phase and shortening of it in antiferroelectric phase.