以一种具有偶氮基团的棒状液晶分子——甲基苯酰氧基偶氮苯甲酸为待测样品,通过紫外吸收光谱法,研究了该化合物在不同极性溶剂中完成反式-顺式异构化过程的紫外光照时间和紫外吸收光谱的变化。结果表明,该化合物的紫外吸收强度以及最大吸收波长与溶剂的极性有关,在极性较强的溶剂中,样品的反式结构及顺式结构的吸收向长波方向移动。
A rod-like liquid crystal molecules with azo groups- methyl benzoyl oxy azo benzoic acid as the sample was tested in this paper. Under exposure of UV-light, the time and UV spectrum changes of the trans- cis isomerization of the compounds in solvents of different polarities were determined by UV-visible spectrometer. The result shows that the intensity and maximum absorption wavelength of the compound in UV spectra have a rela-tionship with the polarity of the solvent. In a solvent with strong polarity, the absorption wavelengths of the trans and cis isomers have a tendency to move to longer wavelength.