title: A strategy for improving the room-temperature luminescence properties of Ru(II) complexes with tridentate ligands.
abstract: Several ruthenium(II) complexes with new tridentate polypyridine ligands have been prepared, and their photophysical properties have been studied. The new tridentate ligands are tpy-modified systems (tpy = 2,2':6',2' '-terpyridine) in which aromatic substituents designed to be coplanar with the tpy moiety are introduced, with the aim of enhancing delocalization in the acceptor ligand of the potentially luminescent metal-to-ligand charge-transfer (MLCT) state and increasing the MLCT-MC energy gap (MC = metal-centered excited state). Indeed, the Ru(II) complexes obtained with this new family of tridentate ligands exhibit long-lived luminescence at room temperature (up to 200 ns). The enhanced luminescence properties of these complexes support this design strategy and are superior to those of the model Ru(tpy)22+ compound and compare favorably with those of the best Ru(II) complexes with tridentate ligands reported so far.
authors.affiliation: Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada.
authors.forename: Yuan-Qing
authors.initials: YQ
authors.lastname: Fang
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Taylor
authors.forename: Garry S
authors.initials: GS
authors.lastname: Hanan
authors.forename: Frédérique
authors.initials: F
authors.lastname: Loiseau
authors.forename: Rosalba
authors.initials: R
authors.lastname: Passalacqua
authors.forename: Sebastiano
authors.initials: S
authors.lastname: Campagna
authors.forename: Hélène
authors.initials: H
authors.lastname: Nierengarten
authors.forename: Alain
authors.initials: A
authors.lastname: Van Dorsselaer