ABSTRACT
There are very few papers discussing the polarization spectra of azomethines. The scope of information on dichroism of this series of dyes is very limited. The overwhelming majority of the merocyanine dyes investigated exhibit a low positive dichroism in liquid crystals. In the polarization spectra of dichroic dye (DD) of Structure 65 — as compared to that of its dilute isotropic solution — new absorption bands appear, which the authors believe are due to the associates. The unsubstituted azulene has an absorption band in the region of 600 nm polarized along the axis y. This absorption band may have different structures, depending somewhat on the conditions under which the spectrum was recorded, but mostly on the nature of the solvent. In nonpolar solvents it has an explicit fine structure. A great number of 1,2,4,5-tetrazines, most containing different substituents.
