A series of discotic octa-and tetra-alkylthio substituted phthalocyanines containing four Cl, Br, I atoms or twelve fluorine atoms have been prepared. All compounds display columnar mesomorphism as confirmed by polarized optical microscopy, thermal analysis, and variable temperature X-ray diffraction. Phthalocyanines containing halide atoms do not crystallize but form glassy or partially crystalline hexagonal columnar phases. Glass transition ...
