Emissive Ruthenium-Bisdiimine Complexes with Chelated Thioether Donors
Journal article, 2016
The photophysical properties of ruthenium(II) complexes of bidentate 2-[(alkylthio)methyl]pyridine (N,S) ligands have been systematically investigated. The co-ligands in the heteroleptic complexes were diimines (N,N ligands, e.g., bpy, phen) or tripodal tetradentate tris(2-pyridylmethyl)amine (tpa). Their X-ray structures revealed little variation in the Ru-S (2.31-2.33 angstrom) and Ru-N (2.06-2.11 angstrom) bond lengths. Despite this, considerable variation can be observed in the electrochemistry and spectroscopy measurements. The presence of the thioether sulfur donor results in a shift to a more positive potential of the Ru2+/Ru3+ process, and the absorption maxima are consequently blueshifted in [Ru(N,N)(2)(N,S)](2+) complexes compared with the [Ru(N,N)(3)](2+) analogues. The [Ru(N,N)(2)(N,S)](2+) complexes display strong room-temperature emission from (MLCT)-M-3 states, governed by the N,N donors. This is corroborated by low-temperature steady-state emission studies, which revealed typical (MLCT)-M-3 emission profiles and excited-state lifetimes of around 5-10 mu s.
Ruthenium
Electrochemistry
LIGAND
ENERGY-GAP LAW
Photophysics
PHOTOCHEMISTRY
NONRADIATIVE DECAY
S ligands
PYRIDYLAMINE COMPLEXES
DELOCALIZATION
OXYGENATION
POLYPYRIDINE COMPLEXES
Synthetic methods
N
PHOTOPHYSICAL PROPERTIES
EXCITED-STATE DECAY
Author
Joachim Wallenstein
Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry
J. Sundberg
University of Southern Denmark
C. J. McKenzie
University of Southern Denmark
Maria Abrahamsson
Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry
European Journal of Inorganic Chemistry
1434-1948 (ISSN) 10990682 (eISSN)
Vol. 2016 6 897-906Areas of Advance
Nanoscience and Nanotechnology
Subject Categories
Chemical Sciences
DOI
10.1002/ejic.201501256