E. Fontes, P. A. Heiney, M. Ohba, J. N. Haseltine, and A. B. Smith, III, Phys. Rev. A37, 1329-1334 (1988).
We present x-ray diffraction measurements of freely suspended single-orientation columnar-phase strands of 2,3,7,8,12,13-hexa(-n-tetradecanoyloxy)truxene [(C13H27COO)6-TX] which show a dramatic difference bwteen the ordering of the rigid, planar central cores and the flexible hydrocarbon chain tails of the molecules. Diffraction from the strands reveals two types of behavior: the tails are highly disordered, producing a nearly isotroipc scattering pattern, whereas the rigid cores are orientationally ordered and translationally disordered within the columns. High-resolution diffraction measurements show that the hexagonal lattice correlation length is greater than 4000 Angstorms, corresponding to more than 200 columns.