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Eu(III) emission band changes caused by peripheral C-H/O hydrogen bonding
Yusuke Kuramochi1, Tetsuya Nakagawa, Toshiaki Yokoo
1Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0101, Japan. kuramo@kitasato-u.ac.jp
Dalton Transactions (Cambridge, England : 2003)
|April 24, 2012
Summary
We synthesized novel Europium(III) and Samarium(III) complexes with phosphine oxide ligands, achieving high luminescence quantum yields. Structural analysis revealed hydrogen bonding influencing the Eu(III) emission spectrum.
Area of Science:
- Coordination Chemistry
- Luminescent Materials Science
- Lanthanide Chemistry
Background:
- Lanthanide complexes are crucial for luminescent applications.
- Tridentate phosphine oxide ligands offer unique coordination environments.
- Understanding structure-property relationships in lanthanide complexes is key.
Purpose of the Study:
- Synthesize and characterize novel Eu(III) and Sm(III) complexes.
- Investigate the luminescent properties of these complexes.
- Determine the impact of ligand environment and hydrogen bonding on luminescence.
Main Methods:
- Synthesis of Eu(III) and Sm(III) complexes with hexafluoroacetylacetonato (hfa) and tris(diphenylphosphinyl)methane (TPPM) ligands.
- Photoluminescence spectroscopy to measure emission quantum yields and spectral profiles.
- X-ray single crystal diffraction to elucidate the coordination structure and intermolecular interactions.
Main Results:
- Achieved high emission quantum yields for both Eu(III) (30%) and Sm(III) (4.7%) complexes.
- Eu(III) complex exhibited nona-coordination with C-H/O hydrogen bonding.
- Observed a red shift in the Eu(III) (5)D(0)→(7)F(2) emission band due to subtle structural changes.
Conclusions:
- Tridentate phosphine oxide ligands facilitate high luminescence in Eu(III) and Sm(III) complexes.
- C-H/O hydrogen bonding influences the coordination sphere and emission characteristics.
- The Eu(III) (5)D(0)→(7)F(2) transition is a sensitive probe for structural modifications.
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