Martin Jarenmark
Forskningsingenjör
Excited State Dynamics of Bistridentate and Trisbidentate RuII Complexes of Quinoline-Pyrazole Ligands
Författare
Summary, in English
Three homoleptic ruthenium(II) complexes, [Ru(Q3PzH)3]2+, [Ru(Q1Pz)3]2+, and [Ru(DQPz)2]2+, based on the quinoline–pyrazole ligands, Q3PzH (8-(3-pyrazole)-quinoline), Q1Pz (8-(1-pyrazole)-quinoline), and DQPz (bis(quinolinyl)-1,3-pyrazole), have been spectroscopically and theoretically investigated. Spectral component analysis, transient absorption spectroscopy, density functional theory calculations, and ligand exchange reactions with different chlorination agents reveal that the excited state dynamics for Ru(II) complexes with these biheteroaromatic ligands differ significantly from that of traditional polypyridyl complexes. Despite the high energy and low reorganization energy of the excited state, nonradiative decay dominates even at liquid nitrogen temperatures, where triplet metal-to-ligand-charge-transfer emission quantum yields range from 0.7 to 3.8%, and microsecond excited state lifetimes are observed. In contrast to traditional polypyridyl complexes where ligand exchange is facilitated by expansion of the metal–ligand bonds to stabilize a metal-centered state, photoinduced ligand exchange occurs in the bidentate complexes despite no substantial MC state population, while the tridentate complex is extremely photostable despite an activated decay route, highlighting the versatile photochemistry of nonpolypyridine ligands.
Avdelning/ar
- Berggrundsgeologi
- Kemiska institutionen
- eSSENCE: The e-Science Collaboration
- Beräkningskemi
- NanoLund: Centre for Nanoscience
Publiceringsår
2019-12-04
Språk
Engelska
Sidor
16354-16363
Publikation/Tidskrift/Serie
Inorganic Chemistry
Volym
58
Issue
24
Dokumenttyp
Artikel i tidskrift
Förlag
The American Chemical Society (ACS)
Ämne
- Theoretical Chemistry
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 1520-510X