Singlet Energy Transfer in Anthracene-Porphyrin Complexes: Mechanism, Geometry, and Implications for Intramolecular Photon Upconversion
Journal article, 2019

In this work we show that the mechanism for singlet excitation energy transfer (SET) in coordination complexes changes upon changing a single atom. SET is governed by two different mechanisms; Förster resonance energy transfer (FRET) based on Coulombic, through-space interactions, or Dexter energy transfer relying on exchange, through-bond interactions. On the basis of time-resolved fluorescence and transient absorption measurements, we conduct a mechanistic study of SET from a set of photoexcited anthracene donors to axially coordinated porphyrin acceptors, revealing the effect of coordination geometry and a very profound effect of the porphyrin central metal atom. We found that FRET is the dominating mechanism of SET for complexes with zinc-octaethylporphyrin (ZnOEP) as the acceptor, while Dexter energy transfer is the dominating mechanism of SET in a corresponding ruthenium complex (RuOEP). In addition, by analyzing the coordination geometry of the complexes and its temperature dependence, the binding angle potential energy of axially coordinated porphyrin complexes could be estimated. The results of this study are of fundamental importance and are discussed with respect to the consequences for developing intramolecular triplet-Triplet annihilation photon upconversion in coordination complexes.

Potential energy

Porphyrins

Ruthenium compound

Anthracene

Temperature distribution

Energy transfer

Photons

Forster resonance energy transfer

Author

Fredrik Edhborg

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry

Betül Kücüköz

Chalmers, Physics, Bionanophotonics

Victor Gray

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry

Bo Albinsson

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry

Journal of Physical Chemistry B

1520-6106 (ISSN) 1520-5207 (eISSN)

Vol. 123 46 9934-9943

Subject Categories

Inorganic Chemistry

Physical Chemistry

Atom and Molecular Physics and Optics

Theoretical Chemistry

Chemical Sciences

Areas of Advance

Nanoscience and Nanotechnology

DOI

10.1021/acs.jpcb.9b07991

More information

Latest update

6/25/2020