title: Biscyclometalated ruthenium complexes bridged by 3,3',5,5'-tetrakis(N-methylbenzimidazol-2-yl)biphenyl: synthesis and spectroscopic and electronic coupling studies.
abstract: A series of biscyclometalated ruthenium complexes bridged by the title ligand were prepared by either an oxidative dimerization of corresponding monometallic complexes or treatment of the bridging ligand with Ru(L)Cl(3) (L = capping ligand). The electronic properties of these complexes were examined by electrochemical and spectroscopic analysis and DFT/TDDFT calculations. The degree of metal-metal electronic coupling of these complexes was estimated on the basis of intervalence charge-transfer transition analysis of corresponding mixed-valent complexes. These studies indicated that the electronic coupling was strongly dependent on the electronic nature of the terminal ligands. A hole-transfer superexchange mechanism was used to understand the underlying electron-transfer processes.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: Jiang-Yang
authors.initials: JY
authors.lastname: Shao
authors.forename: Wen-Wen
authors.initials: WW
authors.lastname: Yang
authors.forename: Jiannian
authors.initials: J
authors.lastname: Yao
authors.forename: Yu-Wu
authors.initials: YW
authors.lastname: Zhong