Coexistence of Förster and Dexter Energy Transfer Pathways from an Antenna Ligand to Lanthanide Ion in Trivalent Europium Complexes through Phosphine-Oxide Bridges

15 April 2020, Version 1
This content is a preprint and has not undergone peer review at the time of posting.


Trivalent europium (Eu3+) complexes are attractive materials for luminescence applications if energy transfer from antenna ligands to the lanthanide ion is efficient. However, the microscopic mechanisms of the transfer remain elusive and fundamental physical chemistry questions still require answers. We track the energy transfer processes in a luminescent complex Eu(hfa)3(DPPTO)2 (hfa: hexafluoroacetylacetonate, DPPTO: 2-diphenylphosphoryltriphenylene) using time-resolved photoluminescence spectroscopy. In addition to the conventional Dexter-type energy transfer pathway through the T1 state of the ligands, we discovered the Forster energy transfer pathway from the S1 of the DPPTO ligands to the 5D1 state of Eu3+ through the weak electronic interaction of a phosphine-oxide bridge. The short timescale of the energy transfer (16 ns, 127 ns) results in its high quantum yield. The coexistence of the distinct energy transfer pathways from a single chromophore is important for establishing design strategies of luminescent complexes.


Ultrafast Spectroscopy
Lanthanide Complex
Electron Transfer

Supplementary materials

200304 EuhfaDPPTO TRPL SI 22


Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.