| 摘要: | 本論文系列一合成設計出含有benzimidazole衍生物的配位基和金屬錯合物(銅、鈀、鎳)，藉由改變側鏈基的長短，而討論其液晶之行為，並透過DSC、POM、XRD等儀器來觀察其液晶在不同溫度下的性質。研究發現，所有含有benzimidazole衍生物的配位基雖不具有液晶相，但具有發光性質，而所有銅和鈀的金屬錯合物均具有SmA液晶相，然而當側鏈基長碳鏈數量為10和12時，鎳金屬錯合物具有Colh液晶相。 系列二與系列三合成出具有α,β-diketone結構之配位基和金屬錯合物(銅、鎳、釩氧)，系列二主要改變側鏈基支數與長短，討論其液晶相之變化，而系列三則改變不同取代基，來研究其液晶相之影響。同樣利用DSC、POM、XRD等儀器來觀測其液晶相行為。結果發現系列二之配位基4a當支數為六支時，n = 6, 8, 10, 12皆具有Colh液晶相，當與金屬(銅、鎳)配位時則會增加液晶相範圍，有助於形成液晶相。而系列三之配位基皆不具液晶相，而金屬錯合物(銅、鎳、釩氧)為Col液晶相，且取代基的導入會使得液晶相範圍變廣，有易於液晶相形成。 In series I the synthesis, characterization and mesomorphic behavior of a series of benzimidazole derivatives 2 and their complexes 1 (M = Cu, Pd, Ni) are described. These compounds have various alkoxy chains attached, and the mesophase exhibited depended on the numbers of alkoxy chains. The mesomorphic properties were investigated using polarized optical microscopy (POM), differential scanning calorimetry (DSC), powder X-ray diffraction (XRD). The results indicated that all ligands based on benzimidazole were not mesogenic. All copper (II) and palladium (II) complexes showed smectic A (SmA) mesophase. However, nickel (II) comlexes with carbon length of n = 10, 12 showed hexagonal columnar mesophase (Colh). The difference in observed mesomorphic behavior might result from the geometry of central core; Cu(II) and Pd(II) ions prefer the square planar geometry, whereas the nikel(II) ion prefer the tetrahedral geometry. In series II and series III, we succeed to synthesize the α,β-diketone derivatives and their complexes (M = Cu, Ni, VO). The results indicated that ligand 4a with carbon length of n = 6, 8, 10, 12 exhibited columnar mesophase.All Copper(II), nickel(II), oxovanadium(II) complexes also exhibited columnar mesophase. In addition, the mesomorphic properties would increase through coordinating with different metals. In series III, the mesomorphic properties observed by these compounds were found to be strongly dependent on the substituent group. The results indicated the the ploarity would be helpful for mesomorphic properties. |
