Further Investigation of Mesophase of Pyramidic Liquid Crystal by X-Ray Transmission Diffractometry

Further X-ray powder diffractometer measurements have been made on compound II-9 of the columnar liquid crystal series hexaalkanoyloxytribenzocyclononene. For this compound the transition temperature between the solid and the columnar phase is 26 degrees C. Data have been collected at several temperatures from 2 degrees C to 52 degrees C. We compare results obtained from II-9 with results published for II-10, 12, 13 and 15. Unlike these other compounds, in the mesophase the diffraction patterns show a large number of lines, with at least four high angle lines superposed on the broad hump arising from scattering by the disordered hydrocarbon side chains. This indicates a more highly ordered structure than for the other compounds in this series.