Mesocrystalline cyanodiphenyl moiety was introduced to the periphery of tetrathiofuvalene (TTF) to successfully synthesize three new liquid crystal compounds. Their structures were fully characterized by means of NMR, FTIR and MALDI-TOF-MS methods. The liquid crystal phase state of the compounds was studied by differential scanning calorimetry (DSC), hot stage polarizing microscopy (HS-POM) and small angle X-ray scattering (SAXS) experiment. The results demonstrated that the synthesized compounds in the wide range of temperature displayed a single liquid crystal phase and in the cooling process did not appear crystallization phenomenon, but transformed into the glass state. The change of linker length had significant influence on the phase state of liquid crystal compounds. The results illustrated that compound with shorter linker represented smectic A phase (SmA) , while compound with longer spacer (1c) presented hexagonal columnar mesophase. The density functional theory (DFT) was used to calculate the electron structure and the electron density distribution of molecular frontier orbital of compound 1a. The results showed that the electron cloud density of the HOMO orbital of compound 1a was concentrated on TTF, and that of LUMO was concentrated on cyanobenzene, indicating that such liquid crystal molecules were typical D-sigma-A molecules.
[1]Changchun Univ Technol, Coll Chem & Life Sci, Changchun 130012, Jilin, Peoples R China.
[2]Changchun Univ Technol, Adv Inst Mat Sci, Changchun 130012, Jilin, Peoples R China.
[3]Jilin Univ, China Japan Union Hosp, Changchun 130033, Jilin, Peoples R China.
(8.0+极速模式)