低聚炔基芴衍生物电子光谱的理论研究

运用密度泛函(DFT)B3LYP方法、从头算单激发组态相互作用(CIS)方法分别优化了炔基取代芴的单体和三聚体的基态及最低激发单重态几何结构.系统分析了分子结构、前线分子轨道特征以探索电子跃迁机理.应用含时密度泛函理论(TD-DFT)计算了分子的电子光谱,得到三聚芴炔的最大吸收及发射光谱分别为417和447 nm,与实验结果接近.同时探讨了单体和低聚体系不同的发光特征,指出炔基芴的低聚体系是良好的蓝光材料.

Theoretical study on electronic spectrum property for oligomeric alkynyl fluorene

The molecular structures of the ground state and the first singlet excited state for oligomeric alkynyl fluorene and it's monomer were optimized with the DFT B3LYP method and ab initio "configuration interaction with single excitations" (CIS) method respectively. The frontier molecular orbital characteristics and energy levels of model systems have been analyzed systematically in order to study the electronic transition mechanism. Electronic spectrum properties of complexes have been investigated with time-dependent density functional theory (TD-DFT). The maximun absorption and emission spectrum of mono-alkynyl fluorine is obtained at 313 and 341 nm, which is in excellent agreement with the experimental values. The theoretical results reveal different luminescent characteristics between monomer and oligomer and suggest that oligomeric alkynyl fluorene should be good blue-light material.