由于其对诸如温度,机械力以及电场和磁场之类的外部刺激的敏感性,表现出热致液晶性质的分子已经变得非常重要。结果,通过在芳族核附近以及在侧链中引入各种官能团,已经合成了几种新颖的介晶,并且已经研究了它们的性质。在本研究中,我们报告了在一个末端带有羟基的三环液晶元。这些介晶通过多步路线合成,并通过光谱技术完成结构表征。通过热阶段光学偏振显微镜,差示扫描量热法和小角X射线散射研究了中间相性质。较低的同系物发现了对映向列相,而较高的同系物则发现了另外的近晶C相。固态高分辨率自然丰度已经对固相和中间相中典型的液晶元进行了13 C NMR研究。层列碳相和向列相的液晶元的13 C NMR光谱表明该分子在磁场中自发排列。通过利用称为SAMPI4的二维分离局部场(SLF)NMR实验,获得了13 C– 1 H偶极耦合,这些耦合用于确定液晶元的取向顺序参数。
Liquid crystalline complexes of octahedral manganese(I)
作者:Duncan W. Bruce、Xiao-Hua Liu
DOI:10.1039/c39940000729
日期:——
Liquid crystalline metal complexes of MnI are reported which comprise an aromatic imine bound in an orthometallated fashion to a Mn(CO)4 moiety; these are unique examples of calamitic thermotropic liquid crystals containing a metal with a simple octahedral coordination environment.
Synthesis and mesomorphic properties of novel Schiff base liquid crystalline EDOT derivatives
作者:Ashwathanarayana Gowda、Arun Roy、Sandeep Kumar
DOI:10.1016/j.molliq.2016.11.010
日期:2017.1
Herein, we reported novel banana liquid crystals derived from ethylenedioxythiophene (EDOT) central unit encompass with Schiff base. Structural charecterization of these compounds was carried out from their spectral and elemental analysis. Physical properties of all the newly synthesized compounds were investigated by polarising optical microscopy, differential scanning calorimetry, thermogravimetric
The synthesis, mesomorphism and mesophase structure of anisotropic imines and their complexes with rhenium(i)
作者:Xiao-Hua Liu、Benoît Henirich、Ian Manners、Daniel Guillon、Duncan W. Bruce
DOI:10.1039/a908137b
日期:——
Highly anisotropic imine ligands have been synthesised and complexed to Re(I). Two series of ligands and complexes were obtained with various chain lengths, showing smectic and nematic phases for the ligands and only a nematic phase for the complexes. The identity of the crystal smectic phase in the ligands was studied by X-ray diffraction and identified as a crystal J phase.
Synthesis, mesophase behavior, and computational studies of dimers composed of three-ring rod-shaped ester-imine linkage monomeric unit
作者:Banti Baishya、Harkishan Dua、Utpal Sarkar、Manoj Kumar Paul
DOI:10.1016/j.molstruc.2024.138754
日期:2024.10
New symmetrical liquid crystal dimers composed of three-ring ester imine rod-shaped monomers with flexible alkyl chains of different parity were synthesized. The thermal stability of the newly synthesized compounds was determined using thermogravimetric analysis. The phase transition and mesogenic behavior of the compounds were explored using polarising optical microscopy and differential scanning
合成了由具有不同奇偶性的柔性烷基链的三环酯亚胺棒状单体组成的新型对称液晶二聚体。使用热重分析测定了新合成化合物的热稳定性。使用偏光光学显微镜和差示扫描量热法探索了化合物的相变和介晶行为。具有奇数奇偶校验间隔基的二聚体表现出相序 Iso-N-N-SmX-Cr。通过偏光光学显微镜观察N相变。这种转变与单轴向列相的转变不同。具有偶校验间隔基的二聚体中不存在 N 相。通过密度泛函理论研究,研究溶剂的稳定构型以及对分子结构参数、化学反应参数和激发态性质的影响。
Effect of hydrogen-bonded supramolecular assembling on liquid crystal properties of imidazole-containing azomethines and their chelates with copper(II)
作者:Oleg N. Kadkin、Jigeon Tae、Eun Ho Kim、So Yeon Kim、Moon-Gun Choi
DOI:10.1080/10610270802709386
日期:2010.1
A series of imidazole-containing rod-like Schiff's bases and their ionic copper(II) chelates with various lengths of the terminal alkyl chain containing 6, 8, 10, 12, 14 and 16 carbon atoms have been synthesised. The synthesised compounds were characterised by elemental analyses, H-1 NMR, IR and UV-vis and mass spectroscopies. Thermotropic smectic C mesophases in the ligands and smectic A mesophases in the copper(II) complexes were identified using POM, DSC and small-angle XRD scattering methods. X-ray diffraction patterns of the prepared imidazole imines indicate to supramolecular self-assembled structures in the liquid crystal state, which are formed by means of intermolecular hydrogen bonds. It was established that both liquid crystal arrangement and supramolecular assemblies in ligands disappeared near 190 degrees C, mainly regardless of the lengths of the terminal alkyl chains. Contrary, assembling of the copper(II) complexes into supramolecular bilayers occurs near 200 degrees C, which causes their transition to a smectic A mesophase.