[Os(N^N)(CO)_2I_2]配合物的密度泛函理论研究  

The Density Functional Theory Study on a Series of [Os( N^N) (CO)_2I_2] Complexes

作　　者：金丽[1] 张建坡[1] 李岩[1] 郝希云[1] 孙秀云[2] 白福全[3] 

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 [2]吉林化工学院科研处,吉林吉林132022 [3]吉林大学理论化学计算国家重点实验室,吉林长春130023

出　　处：《吉林化工学院学报》2013年第9期4-8,共5页Journal of Jilin Institute of Chemical Technology

基　　金：吉林大学理论化学计算国家重点实验室开放课题基金资助(No.20130023)

摘　　要：采用DFT和TD-DFT方法对一系列锇配合物[Os(N^N)(CO)2I2]的基态和激发态几何结构、电子结构、吸收光谱和发射光谱进行了系统的理论研究.计算结果显示出,变换配合物1-3的N^N配体,只是些微的影响了基态和激发态的几何结构,但是导致了较大的电子结构的差异.配合物1-3的最高占据分子轨道(HOMO)主要由Os原子和CO配体共同占据,而三个配合物的最低空轨道(LUMO)都占据在N^N配体上.因此三个配合物的最低能吸收(488(1),474(2)和559 nm(3))被指认为MLCT/LLCT混合电荷转移跃迁.并且,1-3的最低能发射分别位于585、557和611 nm,具有3[π*(N^N)→d(Os)]和3ππ*(3MLCT/3LLCT)的混合跃迁特征,这和最低能吸收的跃迁特性相一致.DFT theory and TD-DFT approach were employed to study the geometry and electronic structures of both the ground and the excited states, and the absorption and emission spectral of [Os（N^N） （CO） 2I2] complexes. The calculations indicated that the variation of the N^N ligand for 1 - 3 only slightly changes their geometrical structures in the ground and excited states but leads to a sizable difference in the electronic structures. The highest occupied molecular orbitals （HOMO） were dominantly localized on the Os atom and CO ligand,while the lowest unoccupied molecular orbitals （LUMO） were mainly composed of N^N ligand.Therefore, the lowest-lying absorptions （ 488 （ 1 ）, 474 （ 2 ）, and 559 nm （ 3 ） ） were assigned to the metal to ligand charge transfer （MLCT）/ligand-ligand charge transfer （LLCT） transition for three complexes. It also reveals that the lowest energy emissions of 1 - 3 at 585 nm,557 nm,and 611 nm have the character of mixing 3[π＊（N^N）→d（Os）] and 3ππ＊（3MLCT/3LLCT）transitions, which are identical to the transition properties of the lowest-energy absorptions.

关 键 词：锇(Ⅱ)配合物 电子结构 光谱特征 TD-DFT 

分 类 号：O641.3[理学—物理化学]