Fundamental Measurements on an Aggregated Dye Liquid Crystal: Introduction
نویسنده
چکیده
The nematic liquid crystal phase is a phase of matter in which the particles have a preferred orientational direction, as opposed to the liquid phase, with no preferred direction, and the solid crystal phase, with an ordered lattice structure. In an aggregated dye, or chromonic, liquid crystal, molecules aggregate together, and the aggregates form a liquid crystal. Aggregated dyes that form liquid crystals have been known for some time, but few fundamental measurements have been taken prior to this research. Unlike most liquid crystals, aggregated dye liquid crystals are water-soluble, opening the door to applications of liquid crystals in the fields of biology and medicine. Phase diagram measurements, birefringence measurements, and order parameter measurements were obtained for the aggregated dye liquid crystal, aqueous Sunset Yellow FCF. A general model of the aggregation consistent with both the results of the birefringence measurements and the results of the order parameter measurements is suggested in which the nitrogen-nitrogen double bonds of the molecule are perpendicular to the long axis of the aggregate. This investigation delves into understanding an aggregated dye liquid crystal, a material that forms a liquid crystal at high concentrations due to the interactions between molecules that cause the molecules to aggregate. Measuring some fundamental properties of the liquid crystal, the phase diagram, the birefringence, and the order parameter, the research reported here has shed light on the nature of both the aggregation of the molecules and the nematic liquid crystal phase that the aggregates form.
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تاریخ انتشار 2005