Structures of the Two Discophases of Rufigallol Hexa-n-Octanoate

X-ray diffraction experiments have been performed on the two mesophases DB and DC of the hexa-n-octanotate of rufigallol (RHO). The disk-like molecules form parallel columns, and the mean distance between two neighbouring cores has the largest value observed until now for a columnar mesophase. The structure of the D B phase is similar to that the mesophase of the hexa-n-octanoate of triphenylene, whereas the structure of the monotropic D C phase is a new one in which three different orientations of the molecular core are present.