系列四中則開發具分子間氫鍵之無鏈彎曲形液晶材料。利用分子結構中之極性氰基端與另一分子之氫氧基端形成分子間氫鍵作用力，使得系列四化合物雖不具有一般液晶分子為了提供擾動力所必備之長碳鏈部分，亦可形成液晶相。 Four series of compounds are reported. The first three are based on discotic hexaynylbenzene core and the last series deals with chain-less bent-shaped molecules.. Incorporating carboxylic groups onto the peripherals of hexaynylbenzene affords, hexakis(carboxylphenylethyl)benzene, which is expected to be coupled with polypeptide chains for superstructure formation. In addition, the carboxylic groups are utilized for the formation of hydrogen-bonding with the pyridinyl group of series three compounds to show liquid crystal behaviors. In the second series, one of the peripherals in hexakis(alkoxylphenylethynyl)benzene is modified by alkylthiol in hope to be attached ontogold nanoparticles. The mesogenic behaviors of analogous compounds with different functional groups in the ω-position are discussed. In the third series, one of the side-arms of hexakis(alkoxylphenylethynyl)benzene was replaced with a pyridinylethyne. The substitution has resulted in lower melting and clearing points .
In the last part of this thesis, chainless bent-shaped mesogens are prepared. For achieving mesophases, the dispersive forces are provided by the intermolecular hydrogen bonding and the bending of the core rather than the vibrational freedom of alkyl or alkoxyl chains.
