中文摘要 系列一：成功的合成出新型的香蕉形液晶，化合物1a、1b形成B6相，液晶現象的觀察與分析則藉助熱分析儀 (DSC)、偏光顯微鏡 (POM) 以及粉末X光繞射 (PXRD) 來判斷。同時藉由單晶繞射、光電測試的實驗結果，來探討其排列方式及其物性。 系列二：設計並合成出一系列具有雙naphthalene mesogenic units的對稱性液晶分子，以碳數不同的碳鏈 (spacer) 做為橋接，探討不同的碳鏈長度對液晶分子的影響。所有化合物皆經由1H- 與 13C-NMR光譜、元素分析及質譜分析加以鑑定其結構與純度；而液晶現象的觀察與分析則藉助熱分析儀 (DSC)、偏光顯微鏡 (POM) 以及粉末X光繞射 (PXRD) 來判斷。實驗結果顯示此系列含naphthalene mesogenic unit的對稱性液晶分子呈現出桿狀液晶相。當中間橋接基為m = 5、7或9，同時側鏈基碳數n = 8、10、12或14時化合物具有液晶相。當中間碳鏈數為m = 5 時，出現規則度較高的SmX 相；當中間鏈數增加 m = 7 或 m = 9 時，開始出現 SmC及nematic 相，由此可以發現，當中間的碳鏈數增加時，會影響其分子所產生的液晶相。 系列三：設計並合成出一系列具有salicylalimine的結構與Pd(OAc)2配位而形成之無機桿狀液晶。所有錯合物皆經由1H 與13C-NMR光譜、元素分析及質譜分析加以鑑定其結構與純度，並且進一步利用單晶X光繞射佐證其配位的正確結構。所有之ligands具有nematic phase或smectic C phase之桿狀液晶相。與Pd金屬配位之錯合物也同樣具有nematic phase或smectic C phase；而形成Pd錯合物之後溫度範圍液晶相明顯變寬廣許多，藉由熱分析儀 (DSC) 以偏光顯微鏡 (POM)及粉末X光繞射 (PXRD) 來判斷液晶相的形成。 Abstratct Series 1 : A novel system of symmetric banana-shaped mesogens. The compound 1a and 1b exhibiting B6 phases.These compounds were all characterized by 1H, 13C-NMR spectroscopy, and their mesomorphic properties were studied by differential scanning calorimeter (DSC) and polarized optical microscopy (POM). The power X-ray data and electro-optical measurement gives astounding structural information suggest that previous investigations could be associated. Series 2 : A novel system of symmetric dimers containing naphthalene units connected by terminal Schiff base as a linkage have been synthesized and investigated for their thermal behavior. All compounds were characterized by 1H, 13C-NMR spectroscopy and elemental analysis, and the mesomorphic behavior of these compounds was characterized by polarized optical microscopy and differential scanning calorimetry. All symmetric dimers linked by a methylene spacer -(CH2)m- containing m = 5, 7 and 9 were mesogenic. The formation of mesophase was in fact sensitive to the spacer length, but not to the terminal chains. The dimeric derivatives with methylene spacer (m = 5) exhibited smectic X phase (SmX), identified by mosaic texture under microscope. In contrast, the dimeric derivatives with spacer length m = 7 or m = 9 exhibited smectic C (SmC) and nematic (N) phases, respectively. The results indicated that in these dimers the spacer length shows a remarkable influence more than terminal side-chains on the thermal behavior. Series 3 : We successfully synthesized A copper(II) and palladium(II) complexes derived from 4-dodecyloxy phenyl-2-carboxylic acid-4-[(3,4-didodecyloxyphenylimino)methyl]-3-hydroxyphenylester was prepared and characterized. Liquid crystalline properties of these copper(II) and palladium (II) complexes were studied and investigated by differential scanning calorimeter (DSC) and polarized optical microscopy (POM). The structures of the mesophases for copper(II) and palladium (II) complexes were also characterized and confirmed as nematic phase or smectic C phase.
