Two ruthenium complexes, [Ru(NN)(ttpy)](2+) and [Ru(NN)(daatpy)](2+), have been designed and prepared, where NN is bis(arnine) ligand 4'-toly1-5,5 ''-bis(di-p-anisylamino)-2,2':6',2 ''-terpyridine, ttpy is 4'-tolyl-2,2':6',2 ''-terpyridine, and daatpy is 4'-di-p-anisylamino-2,2':6',2 ''-terpyridine. Complex [Ru(NN)(daatpy)](2+) contains three redox-active amine groups and has been characterized by single-crystal Xray analysis. These two complexes display much-enhanced light absorption capabilities with respect to the prototype compound [Ru(tpy)(2)](2+) (tpy = 2,2':6',2 ''-terpyridine), which has been rationalized on the basis of time-dependent density functional theory calculations. Electrochemical and optical studies showed that there was little electronic coupling between two amine sites in complex [Ru(NN)(ttpy)](2+). On the other hand, a ligand-to-ligand (N -> N/center dot+) charge-transfer band has been observed at 1430 nm for singly and doubly oxidized forms of [Ru(NN)(daatpy)](2+), and an electronic coupling parameter of 1000 cm(-1) was derived using the Hush formula. This band is interpreted as a charge transfer from the neutral amine of the daatpy ligand to oxidized aminium units in the NN ligand.