西佛碱型液晶化合物相变过程中分子排列方式变化的拉曼光谱研究  

Spectroscopic Research on the Arrangement Change of a Chiral Schiff Based Liquid Crystal in the Phase Transitions

作　　者：姜世梅 徐蔚清[1] 田颜清[2] 

机构地区：[1]吉林大学超分子结构与谱学开放研究实验室,长春130023 [2]吉林大学化学系,长春130023

出　　处：《光散射学报》1999年第4期320-334,共15页The Journal of Light Scattering

摘　　要：用变温拉曼光谱对相变过程的研究表明,液晶化合物的初始晶态与熔融后缓慢降温得到的晶态并不吻合,两个状态下分子尾链的构象及刚性核部分的构象不同导致分子的聚集状态不同。西佛碱型液晶化合物VO10相变过程中,在晶态到液晶态相转变过程中,烷氧基尾链链内构象发生突变,同时有序性降低,刚性核部分两个苯环之间的二面角在相变点时发生明显变化,二面角加大。Temperature dependent FT Raman spectroscopy was used to study the conformational changes and the arrangement changes occurring in the crystalline (Cr), smectic(S) and isotropic(I) phases of a chiral schiff based liquid crystal. Wavenumber shifts as well as changes in band intensity were analyzed in terms of intra and inter molecular interactions. Fourier transform(FT) Raman spectroscopy is shown to be a very powerful and valuable technique for the analysis of liquid crystal materials. By temperature dependent FT Raman spectroscopy, we found a new crystalline phase of a chiral liquid crystal compound and studied the intermolecular interaction of this compound in its smectic phases (S A, S * C).

关 键 词：相变 拉曼光谱 液晶 席夫碱 分子排列 

分 类 号：O753.2[理学—晶体学]