Wybrane zasady Schiffa - badanie struktury i dynamiki

Abstract

Properties of liquid crystalline phases of the selected Schiff bases, i.e., nBBAA and nCBAA homologous series and 5BABB, 6BABB, 5BACB and 6BACB compounds, built of two benzene rings connected by the azomethine group, and of alkyloxy chain and halogene atom (B or Cl), are described in the PhD Thesis. In most of the substances the well-ordered smectic B (SmB) phase and the liquid-like smectic A (SmA) phase were observed. In case of the 5BBAA and 6BABB the smectic E (SmE) phase was also found. Influence of the Iso-SmA, Iso-SmB, SmA-SmB and SmB-SmE phase transitions on structural properties and dynamics were studied using various complementary experimental methods. In the first chapter the classification of liquid crystalline mesophases is presented. In the second chapter the results of polarized microscopy observation are discussed. Third chapter describes the results of X-ray diffraction studies. Fourth part presents in detail the rotational dynamics of selected compounds. The last chapter is focused on the results of the infrared spectroscopy (FT-IR) and the two dimensional correlation analysis of the FT-IR spectra. The most important results of the complementary studies are collected in the Summary. In Annex 1 the code (written in java) for the estimation of the unit cell parameters of SmB and SmE phases is presented. In Annex 2 the code (written for the SciLAB console), preparing the two dimensional correlation analysis is shown.