Several new liquid crystalline materials containing one, two or three chiral centres and having one or two lactate groups in the molecular core have been synthesized. Most of the materials show the blue phase, chiral nematic phase, paraelectric smectic A phase and orthogonal hexatic smectic B phase; some possess the ferroelectric SmC* phase. A study of the mesomorphic properties has been performed using differential scanning calorimetry, optical microscopy and X-ray diffraction. The thickness of the smectic layers and the value of the average distance between the long axes of neighbouring molecules were determined. In the SmC* phase, the temperature dependence of spontaneous polarization, spontaneous tilt angle and helical pitch was measured. The influence of the number of lactate groups on mesogenic behaviour has been established.

We present the X-ray study of three series of ferroelectric liquid crystalline materials with a 2-alkoxypropionate chiral group in order to establish the connection of physical properties and the number of carbon atoms in the non-chiral chain. All materials have the ferroelectric SmC Ã phase in a broad temperature range. Using X-ray diffraction of non-oriented samples we have identified low temperature non-tilted SmX phase as the SmB phase. The thickness of smectic layers and value of the average distance between the long axes of neighbouring molecules were determined. The temperature dependence of the layer spacing was studied in all phases.

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The theory of Green's functions (GF) for thin films was formulated, where site indices were different also along the direction of broken symmetry. This approach results in the layer dependence of correlation functions in films, which did not appear in the previous investigations of thin films. The magnetizations of three layer thin ferromagnetic (FM) and four layer thin ferroelectric (FE) films were investigated using the GFs found in this way. It was shown that the transition temperature varies from layer to layer, which is the obvious consequence of the generalization of the formalism of the GF calculation for films.

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