Carbon-13 NMR Study of Liquid Crystals

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This research, part of the Physical Chemistry Experimental Program, will use carbon-13 NMR to study orientational ordering of liquid crystals. The method to be used involves the removal of proton-proton couplings, rapid sample spinning near the magic angle and reduction of carbon-proton couplings, coupled with the use of Fourier transform techniques to resolve peaks of different carbon atoms. Several systems will be studied by this method including nematic liquid crystals in the mesogenic core. The effects of substituents in the side chain of ferroelectric liquid crystals will be correlated with their spontaneous polarization. Orientational ordering of side chain liquid crystal polymers with polyacrylate and polysiloxane backbones will be investigated. Chain ordering calculations based upon molecular field theory will be performed to analyze the experimental results.