| Summary: | 碩士 === 國立高雄師範大學 === 化學系 === 94 === In order to study the influences of the terminal groups such as （S）-（-）-2-Phenyl-1-propanol, R，R- (3-Phenyl-oxiranyl) methanol, 4- benzyl -1- butnaol, 3- benzyl -1- propyl alcohol and 2- benzyl -1- ethyl alcohol on the liquid crystal properties, seven series of novel liquid crystal compound, An, Bn, Cn, Dn, E1n, E2n and Fn were synthesized. Although both series An and Bn of liquid crystal compounds containing chiral center, only a few compounds of series An exhibit a SmC * phase The compounds of the series Bn are composed of a chiral epoxy group. But no SmC * phase can be observed among them. The compounds of four series Cn, Dn, E1n and E2n, are all achiral. The structure difference between the series Cn and Dn is only at the core molecular part. The position of the benzene ring and the biphenyl ring at the core part for these two series is interchanged. While the compounds of series Cn can exhibit a SmC phase, the compounds of series Dn do not possess a SmC phase. Among the series E1n and E2n, only the compounds E12 and E13 have no SmA phase. Most compounds for the series An, Bn, Cn and Dn possess both SmA and N or N * phases.
A series of bent molecules, Fn, was also synthesized. The primary results indicate that they may have the ferroelectric property. These interesting results are worth deeply studying.
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