物理化学学报 >> 2011, Vol. 27 >> Issue (05): 1089-1094.doi: 10.3866/PKU.WHXB20110505

理论与计算化学 上一篇    下一篇

四齿配体[Ru(iph)(L)2]2+ (L=cpy, mpy, npy)配合物的结构和光谱特征

张建坡1, 金丽1, 张红星2   

  1. 1. 吉林化工学院, 化学与制药工程学院, 吉林 吉林 132022;
    2. 吉林大学理论化学研究所, 理论化学计算国家重点实验室, 长春 130023
  • 收稿日期:2011-01-03 修回日期:2011-02-10 发布日期:2011-04-28
  • 通讯作者: 金丽 E-mail:canoe8013@126.com
  • 基金资助:

    理论化学计算国家重点实验室开放课题基金资助项目

Structures and Spectroscopic Properties of [Ru(iph)(L)2]2+ (L=cpy, mpy, npy) Complexes Containing Tetradentate Ligands

ZHANG Jian-Po1, JIN Li1, ZHANG Hong-Xing2   

  1. 1. School of Chemical and Pharmaceutical Engineering, Jilin Institute of Chemical Technology, Jilin 132022, Jinlin Province, P. R. China;
    2. State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Changchun 130023, P. R. China
  • Received:2011-01-03 Revised:2011-02-10 Published:2011-04-28
  • Contact: JIN Li E-mail:canoe8013@126.com
  • Supported by:

    The project was supported by the Foundation of State Key Laboratory of Theoretical and Computational Chemistry, China.

摘要:

采用密度泛函的B3LYP和UB3LYP方法分别优化了一系列[Ru(iph)(L)2]2+ (L=cpy (1), mpy (2), npy (3); 其中iph为2,9-双(1′-甲基-2′-咪唑)-1,10-邻二氮杂菲, cpy为4-氰基嘧啶, mpy为4-甲基嘧啶, npy为4-氮二甲基嘧啶)配合物的基态和激发态结构. 利用含时密度泛函理论(TD-DFT)方法, 结合极化连续介质(PCM)模型计算了它们在丙酮溶液中的吸收和发射光谱. 研究结果表明: 优化得到的几何结构参数和相应的实验值符合得非常好. 1和2的最高占据分子轨道主要由金属的d轨道和iph配体的π轨道构成, 但是3主要占据在npy配体上, 而它们的最低空轨道主要由iph配体的π反键轨道占据. 因此, 1和2的最低能吸收和发射属于金属到配体(MLCT)和配体内部(ILCT)的电荷转移跃迁, 而3属于两个配体之间的电荷转移(LLCT)跃迁. 三个配合物的最低能吸收分别在509 nm (1), 527 nm (2)和563 nm (3), 其磷光发射分别在683 nm (1), 852 nm (2)和757 nm (3). 这显示出通过调节L配体的π电子给予能力可以改变最低能吸收和发射的跃迁性质和发光颜色.

关键词: 四齿配体Ru配合物, 激发态, 含时密度泛函理论, 光谱特征, 电荷转移

Abstract:

The geometries of ground and excited states of a series of ruthenium complexes [Ru(iph)(L)2]2+(L=cpy (1), mpy (2), npy (3); iph=2,9-di(1-methyl-2-imidazole)-1,10-phenanthroline, cpy=4-cyano pyridine, mpy=4-methyl pyridine, npy=4-N-methyl pyridine) were optimized by the Becke′s three-parameter functional and the Lee-Yang-Parr (B3LYP) functional and unrestricted B3LYP methods, respectively. Time- dependent density functional theory (TD-DFT) method at the B3LYP level together with the polarized continuum model (PCM) were used to obtain their absorption and phosphorescent emission spectra in acetone media based on their optimized ground and excited-state geometries. The results revealed that the optimized structural parameters agreed well with the corresponding experimental results. The highest occupied molecular orbitals were localized mainly on the d orbital of the metal and the π orbital of the iph ligand for 1 and 2, and the npy ligand for 3, while the lowest unoccupied molecular orbitals were mainly composed of π* orbital of the iph ligand. Therefore, the lowest-lying absorptions and emissions were assigned to the metal to ligand charge transfer (MLCT)/intra-ligand charge transfer (ILCT) transition for 1 and 2, and the ligand to ligand charge transfer (LLCT) transition for 3. The lowest-lying absorptions are at 509 nm (1), 527 nm (2), and 563 nm (3) and the phosphorescence emissions at 683 nm (1), 852 nm (2), and 757 nm (3). The calculation results show that the absorption and emission transition characteristics and the phosphorescence color can be changed by altering the π electron-donating ability of the L ligand.

Key words: Tetradentate ligands Ru complexes, Excited state, Time-dependent density functional theory, Spectroscopic property, Charge transfer

MSC2000: 

  • O641