8-巯基喹啉阴离子的锌配合物及其衍生物的电子光谱性质的含时密度泛函理论研究

采用从头算(ab initio)和密度泛函理论(DFT B3LYP)方法, 对配合物8-巯基喹啉锌Zn(tq)₂及其5种衍生物基态结构进行优化, 用含时密度泛函理论(TD-DFT/B3LYP)及6-31＋G(d)基组计算吸收光谱; 同时用ab initio HF 单激发组态相互作用(CIS)法在6-31G(d)基组上优化其最低激发单重态几何结构, 用含时密度泛函理论计算发射光谱. 结果表明, 电子在基态与激发态间的跃迁, 主要是在配体8-巯基喹啉(tq)环内的电荷转移, 电子从含S的苯硫酚环转移至含N的吡啶环上; 吸收光谱和发射光谱的计算值与实验值基本符合. 该类配合物都是优良的电子传输材料, 改变金属离子和取代基均可以调控发光材料的光谱波段.

TD-DFT Study on Electronic Spectrum Properties of Zinc Complex with 8-Thiolquinoline Anion and Its Derivatives

Luminescent organic/organometallic compounds have attracted much attention recently because of their applications to electroluminescent display. The most well-known example of such chelate com- pounds is Alq3, q=deprotonated 8-hydroxyquinoline, a green emitter and an electron transporter in organic EL devices. The structures of zinc complex with 8-thiolquinoline anion Zn(tq)2] and its derivatives were optimized in the ground state using ab initio HF and B3LYP methods, and absorption spectra based on the above structures were obtained by the time-dependent density functional theory (TD-DFT) by the B3LYP method with the 6-31 G(d) basis set. At the same time, the molecular structure of the first singlet excited state for Zn(tq)2 and its derivatives was optimized by CIS/6-31G(d), and the EL peak could be obtained by the emission spectrum with TD-B3LYP/6-31G(d) method. The calculated results indicated that the lumines- cence originates from the electronic transition from the thiophenol ring to the pyridine ring. The calculated results of absorption spectrum and emission spectrum for zinc complex with 8-thiolquinoline anion and its derivatives have good agreement with the experimental data. All compounds are excellent electron- transporting materials, luminescence wave bands of which can be tuned by different metals and substituent on the ligand of 8-thiolquinoline anion.