NMRD Studies of Binary Liquid Crystal Mixtures exhibiting Induced Smectic Ad Phases
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چکیده
Chapter 7 presents a study of molecular dynamics as a function of molecular composition in novel binary liquid crystalline mixtures of nematic liquid crystals 8CN and 7BCB, which exhibit Induced Smectic Phase (ISP). Frequency and temperature dependent spin-lattice relaxation time measurements were carried out in pure systems and mixtures at specific compositions. This work is done in collaboration with another researcher in the same laboratory. Data analysis was done considering four different dynamic processes, namely Director Fluctuations (DF), Self-Diffusion (SD), Rotations about the short axis (R) and Frustration (F), in mediating the spin relaxation. Formation and segregation of molecular associations (dimers and clusters) is termed as 'Frustration' in this work.
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