U. Dahn, C. Erdelen, H. Ringsdorf, R. Festag, J. H. Wendorff, P. A. Heiney, and N. C. Maliszewskyj, Liq. Cryst. 19 759-764 (1995).
The concept of mesophase stabilisation by partial fluorination of side chains has been extended towards discotic systems. The mesophase structure is essentially unchanged whereas the temperature range of the mesophase is strongly affected by the fluorinated side chains. Triphenylene substituted with only one partially fluorinated side chain exhibits a decrease of the clearing temperature whereas for symmetrically substituted ones a broad mesophase has been observed. This behavior can be attributed to a segregation of the incompatible parts of the molecule giving rise to a stabilised columnar structure for the symmetrical substitution pattern.