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In this thesis I present four main topics. One is an introduction to liquid crystals and the second is an opto-electronic experimental setup. The third is an investigation of the dynamic properties of dendrimers, which show ferroelectric features. The last one is a research focused on understanding of the structures of two different types of De Vries smectic A liquid crystal phases. All research activities are performed by the hand-made but automatically controlled opto-electronic experimental setup. First, an introduction to liquid crystals is presented in easy language. Mainly there are two kinds of liquid crystals, thermotropic and lyotropic, but I focus only on the thermotropic LCs (liquid crystals) because they are the very materials being used in display industry nowadays and this goes well with my research aim. Second, I present the experimental setup/techniques and the process of making a liquid crystal cell. This part deals with detailed practical laboratory skills concerned with doing investigation of liquid crystals. Third, dendrimers, a new type of liquid crystal, have been receiving a great amount of attention from scientists from many different disciplines. Dendrimers can be utilized in various industries, such as, medicine, display materials, catalysis, inks, nanoelectronics, etc. I specifically focus on the ferroelectric properties of dendrimers, the main feature of LCD industry. As a result I found that optical switching depends on the generation number of the dendrimers. Finally, I propose two possible structures for a new type of LC phase, De Vries smectic A phase. Several materials were found to possess such a phase; however, it was extremely hard to tell which structure those De Vries smectic A liquid crystals have, because of the size of the matters. But I have very satisfying evidence to support two possible molecular arrangement for those De Vries phases using our opto-electronic setup.
Chang, M. (2004). Investigation of novel liquid crystal materials for their possible applications. Masters dissertation. Technological University Dublin. doi:10.21427/D7GD0P