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Haitao Li, Jianxun Wen, Yonggang Yang 

 Mol. Cryst. Liq. Cryst., 2007, 473, 15-22.

         Three series of chiral compounds with semifluorocarbon chains have been synthesized. These compounds were characterized by infra-red spectra (IR), 1H nuclear magnetic resonance (1H NMR), 19F nuclear magnetic resonance (19F NMR), mass spectra (MS), and elemental analysis. Their phase-transition behavior was investigated by differential scanning calorimeter (DSC) and polarizing optical microscopy. To a certain compound, when the terminal hydrogen atom in the semifluoroalkyl chain was substituted by a chlorine atom, both the clearing point and the melting point were increased and the thermal stability of the SmC phase was enhanced. Moreover, with the introduction of a triple bond in the core, both the melting point and the clearing point were increased.