Evaluation of dynamics of liquid crystalline structures by time-resolved X-ray diffraction

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The purposes of this research are (1) the determination of the structures of novel liquid crystalline phases by powerful and small bema X-ray diffraction using the confocal X-ray source, and (2) the evaluation of the layer dynamics of smectic liquid crystals by time-resolved x-ray diffraction using the image intensifier and CCD camera.In the first year, I introduced confocal mirror in order to increase the incident X-ray intensity and to decrease the beam size. In the second year, I introduced the image intensifier and CCD camera in order to measure time resolved x-ray diffraction. At the same time, I measured the x-ray diffraction of the B4 and Bx phases of binary mixture of P-8-0PIMB and 5CB, and the determined the mixing ratio dependence of the structures for two years.In the last year, I measured the terminal chain dependence of the layer structure of bent-shaped dimers. It was found that the structure changes from a single layer to the 2D frustrated one with increasing the terminal chain. Previously, the structure was considered to be bilayer in the compound in which the carbon number of the terminal chain length is 16, but it was found to form frustrated layer even in this compound.With respect to the optically isotropic mesophase called SmBPiso, it has been already found that the selective reflection band was shifted by the laser irradiation. In order to study-the layer response at this process, I measured time-resolved x-ray diffraction of this phase. As a result, the layer response was found to be several hundreds of msec, which is longer than the optical response (several msec).