Theoretical predication on optical and electronic properties of multifunctional molecules for blue-light multifunctional materials

2-(Dimesitylboryl)-9-ethyl-9H-carbazole (CzB), 2-(4-(dimesitylboryl)phenyl)-9-ethyl-9H-carbazole (CzPhB), 2-(5-(dimesityl-boryl)thiophen-2-yl)-9-ethyl-9H-carbazole (CzThB), and (E)-2-(4-(dimesitylboryl)styryl)-9-ethyl-9H-carbazole (CzSB) have been studied by theoretical measurements with GAUSSIAN software. To reveal the relationship between the structures and properties of these multifunctional electroluminescent materials, their geometrical structures of ground and excited-states were optimized by B3LYP/6-31G(d), HF/6-31G(d), and CIS/6-31G(d) methods, respectively. The lowest excitation energies (Eg) and the maximum absorption and emission wavelengths of these compounds were calculated by time-dependent density functional theory methods. The important parameters for luminescent materials were also predicated including the reorganization energies, the ionization potentials and electron affinities. As a result of calculations, these molecules are considered as candidates for excellent OLEDs with good charge-transfer abilities, high blue-light emission and low energy barriers for charge injection, and the phene-based molecule has higher electron mobility and better equilibrium properties as compared to the other compounds.