取代基对过渡金属铱配合物结构和光谱性质的影响  

The Effect of Substitutes Group on the Electron Structures and Spectroscopic Properties of Transition Metal Iridium Complexes

作　　者：丛丽 井玉琪 刘贺 聂建航 张建坡[1] CONG Li;JING Yuqi;LIU He;NIE Jianhang;ZHANG Jianpo(Department of Chemical and Pharmaceutical Engineering,Jilin Institute of Chemical Technology,Jilin City 132022,China)

机构地区：[1]吉林化工学院化学与制药工程学院,吉林吉林132022

出　　处：《吉林化工学院学报》2020年第5期6-10,共5页Journal of Jilin Institute of Chemical Technology

摘　　要：采用DFT和TD-DFT方法研究了一系列(C^N)2Ir(N^N-X)[C^N=2-苯基吡啶,N^N=2-吡啶基-1,3,4-恶二唑,X=氯苯(1)、X=苯基(2)、X=苯乙炔(3)和X=吡啶(4)]配合物的结构和光谱特征.首先采用B3LYP/LanL2DZ泛函优化了配合物1-4的基态几何结构,在此基础上选用UB3LYP/LanL2DZ泛函得到其激发态结构.计算得到的Ir-N(1)和Ir-N(3)基态键长和相应实验值符合得较好.在TD-DFT和PCM计算水平下,得到1-4的低能吸收和发射分别出现在454(1)、446(2)、453(3)、461(4)nm和649(1)、650(2)、642(3)、638(4)nm.这些激发的起始分子轨道HOMO-1主要由苯基吡啶配体(C^N)占据,而终止轨道LUMOs均为π*(N^N)型轨道,因此,该跃迁被指认为π-π*跃迁,具有配体到配体的电荷转移跃迁(LLCT)特征.研究显示出此类配合物的吸收和发射主要由双齿配体本身控制,受X取代群组影响较小.The structures and spectroscopic properties of a series of(C^N)2Ir(N^N-X)[C^N=2-phenylpyridine,N^N=2-pyridyl-1,3,4-oxadiazole,X=chlorobenzene(1),X=phenyl(2),X=phenylyne(3),X=pyridine(4)]complexes were investigated by the DFT and TDDFT methods.We first optimized geometrical structures in ground state of complexes 1-4,at the B3LYP/LanL2DZ levels,and the excited state structures by selected UB3LYP/LanL2DZ functionals.The calculated bond lengths of Ir-N(1)and Ir-N(3)in the ground state agree well with the corresponding experimental results.At the TD-DFT and PCM levels,1-4 give rise to lower energy absorptions at 454(1),446(2),453(3),461(4)nm and corresponding phosphorescent emissions at 649(1),650(2),642(3),and 638(4)nm,respectively.The HOMO-1 of 1-4 are mainly localized on the phenylpyridine(C^N)ligands,while the LUMOs are theπ*(N^N)type orbital.Therefore,the transitions of 1-4 were assigned to theπ-π*transition with ligand-to-ligand charge transfers(LLCT)characters.It is shown that the absorptions and emissions are significantly dominated by the bidentate ligand itself,but are minor impact by the X-substituent group.

关 键 词：1 3 4-恶二唑(OXD) Ir配合物 电子结构 光谱特征 

分 类 号：O641.3[理学—物理化学]