Energy Transfer from Antenna Ligand to Europium(III) Followed Using Ultrafast Optical and X-ray Spectroscopy

Michael William Mara, David S. Tatum, Anne Marie March, Gilles Doumy, Evan G. Moore, Kenneth N. Raymond

Research output: Contribution to journalArticlepeer-review

59 Scopus citations

Abstract

A series of highly luminescent europium(III) complexes which exhibit photoluminescence from the Eu(III) center following energy transfer from the UV absorbing organic sensitizer have been investigated using a combination of ultrafast optical transient absorption and Eu L3 X-ray transient absorption techniques. We have previously demonstrated that the latter can be used as a signature of 4f-4f excitation responsible for the photoluminescence in these Eu(III) coordination complexes, but the long time scale of the earlier measurements did not allow direct observation of the ligand-To-metal energy transfer step, preventing a determination of the sensitization mechanism. Here, we provide the first direct experimental verification that Dexter electron exchange from the ligand triplet state is the dominant energy transfer mechanism in these photoluminescent systems. Moreover, the optical transient absorption results obtained herein imply that energy transfer for all three compounds has near unity yield, regardless of differences in the sensitization efficiencies, suggesting that the variations in the sensitization efficiencies are determined almost entirely by differences in the ligand-centered intersystem crossing rates. The implications for the rational design of more effective photoluminescent lanthanide complexes are discussed.

Original languageEnglish (US)
Pages (from-to)11071-11081
Number of pages11
JournalJournal of the American Chemical Society
Volume141
Issue number28
DOIs
StatePublished - Jun 23 2019

ASJC Scopus subject areas

  • Catalysis
  • General Chemistry
  • Biochemistry
  • Colloid and Surface Chemistry

Fingerprint

Dive into the research topics of 'Energy Transfer from Antenna Ligand to Europium(III) Followed Using Ultrafast Optical and X-ray Spectroscopy'. Together they form a unique fingerprint.

Cite this