Abstract
The synthesis and phase behaviour of a new series of unsymmetrically substituted hexaalkoxytriphenylene-based liquid crystals are reported. One of the hexyloxy chains in hexahexyloxytriphenylene (HAT6) is replaced by either a shorter or a longer chain, HAT-(OC
6
H
13
)
5
(OC
n
H
2n+1
). Compounds with chain lengths n of 2-14, 16 and 18 were prepared and investigated. Compounds with n⩾13 were not liquid crystalline. For all compounds with n⩽12 Col
h
textures were observed by polarizing microscopy. X-ray investigations showed that the intercolumnar distance gradually increased with n from n = 2 to n = 12, while the interdisk distance (3.6 Å) remained constant. A small odd-even effect on the increase of the intercolumn distance with n was observed. This effect was also found in the change of ΔH of isotropization with n.