Simulation Study On Terahertz Absorption Of Liquid Crystal Mixture With Cyano Radical

E7 is a commonly used polar liquid crystal mixture, which has a high optical anisotropy and a wide temperature range of nematic phase. In this work, the absorption characteristics on terahertz band of E7 are studied using the quantum chemistry method, which is called Gaussian98 program based on density functional theory. The terahertz absorption of the constitutional molecular groups were analyzed and compared with the experimental data. The results show that the number of benzene rings and the presence of oxygen atom in the molecular side chain will influence the terahertz absorption strongly in the intensity, the location and number of absorption peaks. Compared with the experimental references, the calculated absorption information of molecular vibration in the lower frequency band is more clear and complete. In the higher frequency band, the absorption of the calculated molecular vibration is agreement well with the experimental data.