吡唑基双环分子态结构及光谱性质的量子化学研究  

Quantum chemical study on the structure and spectral properties of pyrazolyl bicycles

作　　者：于正罡 杨宝珠[1] 陈银娟 殷开梁[1] YU Zheng-Gang;YANG Bao-Zhu;CHEN Yin-Juan;YIN Kai-Liang(Computation Center of School of Petrochemical Engineering,Changzhou University,Changzhou 213164,China)

机构地区：[1]常州大学石油化工学院计算机中心,江苏常州213164

出　　处：《化学研究与应用》2022年第9期2096-2103,共8页Chemical Research and Application

摘　　要：有机电致发光二极管因具特殊的光电功能而被广泛关注,并应用于诸多领域,双环杂环类化合物以其丰富的光物理性质正成为该领域的研究热点。本工作采用含时密度泛函理论,对5种含有吡唑环及六元杂环分子的基态、激发态结构进行了几何优化并计算了环己烷溶剂下的紫外、荧光、磷光等光谱。研究结果表明,取代基及六元环中N原子数量和位置的不同对双环分子的主体结构影响不大,双环基本上共平面;各能级中,五元环和六元环分子轨道占比有显著不同,且取代基占比极少,分子中电子分布性质主要取决于双环构型。不同分子紫外吸收光谱振子强度最大的跃迁对应的能级间隔不同,且N原子的引入对跃迁行为产生显著影响。对其荧光及磷光发射分析发现,六元环上N原子的位置和数量对其斯托克斯位移具有显著调节作用,且当2个氮原子处于对位时,分子的斯托克斯位移最小,双环芳香性最强,其磷光发射谱峰值波长达到665 nm,可作为红光发光的备选材料。Organic light-emitting diodes(OLEDs)have been widely concerned and applied in many fields because of their special photoelectric functions.Bicyclic heterocyclic compounds are becoming a research hotspot in this field because of their rich photophysical properties.In this work,the ground state and excited state structures of five molecules containing pyrazole ring and six membered heterocycle were geometrically optimized by using time-dependent density functional theory,and the UV,fluorescence and phosphorescence spectra in cyclohexane solvent were calculated.The results show that the number and position of N atoms in substituents and six membered rings have little effect on the main structure of bicyclic molecules,and the bicycles are basically coplanar;In each energy level,the molecular orbital proportions of five membered ring and six membered ring are significantly different,and the substitution proportion is very few.The electron distribution in the molecule mainly depends on the double ring configuration.The energy level interval corresponding to the transition with the largest oscillator intensity in the UV absorption spectrum of different molecules is different,and the introduction of N atom has a significant effect on the transition behavior.The fluorescence and phosphorescence emission analysis shows that the position and number of N atoms on the six membered ring can significantly regulate the Stokes shift.When the two nitrogen atoms are in the opposite position,the Stokes shift of the molecule is the smallest,the double ring aromaticity is the strongest,and the peak wave of the phosphorescence emission spectrum is up to 665 nm,which can be used as an alternative material for red luminescence.

关 键 词：有机发光材料 吡唑基双环杂环分子 含时密度泛函 态结构 光谱特性 

分 类 号：O641.12+1[理学—物理化学]