摘要
以密度泛函理论(DFT)和含时密度泛函理论(TDDFT)方法为基础,研究8种含S^S型配体的Pt(Ⅱ)配合物二聚体的磷光发射机制,揭示构效关系,定性探索聚集诱导发光(AIE)机制。结果表明:配合物1、2和3的二聚体的发光特性为^(3)ILCT/^(3)MLCT/^(3)LLCT,配合物4的发光特性为^(3)ILCT/^(3)MLCT,均以^(3)ILCT为主;4种配合物在二氯甲烷溶液中无磷光发射的原因是Stpip上苯环的旋转导致大的非辐射衰变常数,而配合物的聚集限制了苯环旋转;配合物3有最大量子产率的主要原因是其^(3)MLCT成分最大以及单重态和三重态分裂能ΔE_(ST)最小;非稠合主配体ppy适中的共轭扩展程度、稳定的π-π堆积和有效的分子内转动限制有利于产生大的量子产率。
On the basis of the density functional theory(DFT)and time-dependent density functional theory(TDDFT),the phosphorescence emission mechanisms of eight Pt(Ⅱ)complexe dimers with S^S type ligands were investigated to reveal the intrinsic relationship between the photophysical properties and structures,and the mechanism of the aggregation-induced emission(AIE)was explored qualitatively as well.It is found that the natures of the phosphorescence emissions of complexes 1,2,and 3 are^(3)ILCT/^(3)MLCT/^(3)LLCT and the nature of the phosphorescence emission of complex 4 is^(3)ILCT/^(3)MLCT,which are mainly^(3)ILCT.These complexes are not emissive in the dichrolomethane solution due to the large radiationless decay constant caused by the rotation of phenyl rings in the Stpip ligand,which is restricted by the aggregation of complexes.The main reasons for complex 3 having the largest quantum yield are that it has the largest ^(3)MLCT component and the smallest singlet-triplet splitting energyΔE_(ST).The computational results imply that a moderate degree of conjugation extension,stableπ-πstacking,and effective restriction of intermolecular rotation help to produce large quantum yield.
作者
周艳
栾雪垠
乔立歌
张玉贞
ZHOU Yan;LUAN Xueyin;QIAO Lige;ZHANG Yuzhen(School of Chemistry and Chemical Engineering,Guangxi Minzu University,Nanning 530006,China;Guangxi Key Laboratory of Polysaccharide Materials and Modification,Guangxi Minzu University,Nanning 530006,China)
出处
《中国石油大学学报(自然科学版)》
北大核心
2025年第3期232-240,共9页
Journal of China University of Petroleum(Edition of Natural Science)
基金
国家自然科学基金地区项目(22165002)。
关键词
有机发光二极管
密度泛函理论
过渡金属配合物
磷光
聚集诱导发光
OLEDs
density functional theory(DFT)
transition metal complexes
phosphorescence
aggregation-induced emission(AIE)
作者简介
第一作者及通信作者:周艳(1980-),女,副研究员,博士,研究方向为计算化学。E-mail:zhouyan@gxmzu.edu.cn。
