Abstract
We reported that 4-[4-(7-hydroxyheptyloxy)phenyl]-1-(4-hexylphenyl)-2,3-difluorobenzene showed a cybotactic nematic (Ncyb) phase with a temperature range of 8 K 1). To investigate structural effects on stabilizing the Ncyb phase, we have modified the compound. We prepared some 1,4-diphenyl-2,3-difluorobenzene derivatives. The derivative possessing a hexyloxy group and a 6-hydroxyhexyloxy group was found to indue the Ncyb phase with a temperature range of 25 K. On the other hand, the derivative possessing a 4-methylpentyloxy group instead of the hexyloxy group showed a conventional N phase, a monolayered SmC phase, and a bilayered SmC phase. Furthermore, a U-shaped compound possessing two 1,4-diphenyl-2,3-difluorobenzene units was found to exhibit Ncyb and SmC phases. The layer spacing in these phases decreased continuously with decreasing temperature.
