物理化学学报 >> 2009, Vol. 25 >> Issue (10): 2113-2117.doi: 10.3866/PKU.WHXB20090936

研究论文 上一篇    下一篇

Ph3PAuX和Ph3AsAuX(X=Cl, Br)的最低三重激发态

莽朝永, 自俊青, 赵霞, 吴克琛   

  1. 大理学院生命科学与化学学院, 云南 大理 671000|大理学院东喜马拉雅资源与环境研究所, 云南 大理 671000|中国科学院福建物质结构研究所, 结构化学国家重点实验室, 福州 350002
  • 收稿日期:2009-03-04 修回日期:2009-06-11 发布日期:2009-09-29
  • 通讯作者: 莽朝永, 吴克琛 E-mail:cymang@gmail.com; wkc@fjirsm.ac.cn

The Lowest Triplet Excited States of Ph3PAuXand Ph3AsAuX(X=Cl, Br)

MANG Chao-Yong, ZI Jun-Qing, ZHAO Xia, WU Ke-Chen   

  1. College of Life Science and Chemistry, Dali University, Dali 671000, Yunnan Province, P. R. China|Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali 671000, Yunnan Province, P. R. China|State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, P. R. China
  • Received:2009-03-04 Revised:2009-06-11 Published:2009-09-29
  • Contact: MANG Chao-Yong, WU Ke-Chen E-mail:cymang@gmail.com; wkc@fjirsm.ac.cn

摘要:

分子水平上的激发态理论研究能够用来解释分子材料的多色发光机理. 采用单组态相互作用方法, 计算研究了四种二配位的Au(I)配合物Ph3PAuCl, Ph3PAuBr, Ph3AsAuCl和Ph3AsAuBr的分子结构限制的三重激发态(T1a)和分子结构松弛的三重激发态(T1b)的分子结构与光物理性质. 由于θ(PAuX)/θ(AsAuX)从180°扭曲到120°左右, T1b态的能量在单线态组态相互作用(CIS)水平上降低了0.805-1.124 eV, 在密度泛函理论(DFT)水平上降低了0.820-0.947 eV. 自然键轨道电荷布居数分析表明, 在T1a态中两个单电子主要分布在一个苯基上, 而在T1b态中两个单电子分布在PAuX/AsAuX 上. 因此, 在晶体中观察到的较高能磷光归属于T1a态的苯基之间的3π*→1π电子跃迁, 而较低能磷光主要起源于T1b态的Au 的3σ*→1σ电子跃迁.

关键词: 金配合物, 发光, 激发态, 单组态相互作用

Abstract:

A reasonable interpretation of multi-color luminescence mechanisms for molecular materials can be obtained from theoretical research into molecular excited states. Molecular structures and photophysical properties of the restricted (T1a) and relaxed (T1b) lowest triplet excited states of four two-coordinated Au(I) complexes, Ph3PAuCl, Ph3PAuBr, Ph3AsAuCl, and Ph3AsAuBr, were investigated using the single-excitation configuration interaction (CIS) method. Because of a remarkable distortion of the θ(PAuX)/θ(AsAuX) from 180°to about 120°, the T1b state was found to be considerably reduced in energy, e.g. 0.805-1.124 eV using CIS, 0.820-0.947 eV using density functional theory (DFT). An analysis of the natural bond orbital (NBO) electronic spin density indicates that two single electrons mostly populate on one of the three phenyls for the T1a state and on the PAuX/AsAuX fragment for the T1b state. Finally, a higher-energy phosphorescence was observed in the crystals and was assigned to one inter-phenyl 3π*→1πtransition of the T1a state, whereas a lower-energy phosphorescence was mostly due to a 3σ*→1σtransition in the T1b state with a sp2 hybridized Au(I).

Key words: Gold complex, Luminescence, Excited state, Single-excitation configuration interaction

MSC2000: 

  • O641