Development of an equation of state for nematic liquid crystals

Abstract

In this thesis I aim to contribute to a molecular understanding and -description of the phase behaviour of liquid crystalline materials. In particular, I aim at the development of a molecular-based equation of state (EoS) for describing nematic (only orientationally ordered) liquid crystals (LCs) and their mixtures. Special emphasis is put on the role of intra-molecular flexibility on the liquid crystalline phase behaviour. Also, the solubility of small gases in nematic solvents is studied—an area that could be important for potential applications of LCs as novel solvents in gas-absorption processes. In the first part of this introductory chapter, the reader is provided with some background on the liquid crystalline state of matter, the status of LC research, and common and potential applications of LCs (Sections 1.1 and 1.2). Subsequently, available theories for the nematic state are briefly reviewed, and the foundations of the perturbation methodology which is at the basis of the EoS developed in this work are discussed (Section 1.3). Finally, an outline of the work performed in this thesis is presented (Section 1.4).