Role of Ligand-to-Metal Charge Transfer State in Nontriplet Photosensitization of Luminescent Europium Complex
| العنوان: | Role of Ligand-to-Metal Charge Transfer State in Nontriplet Photosensitization of Luminescent Europium Complex |
|---|---|
| المؤلفون: | Xi-Cheng Ai, Li-Min Fu, Jian-Ping Zhang, Man-Yu Li, Rui Hao, Yuan Wang, Xiao-Fan Wen, Yishi Wu |
| المصدر: | The Journal of Physical Chemistry A. 114:4494-4500 |
| بيانات النشر: | American Chemical Society (ACS), 2010. |
| سنة النشر: | 2010 |
| مصطلحات موضوعية: | Luminescence, Kinetics, Analytical chemistry, chemistry.chemical_element, Gadolinium, Ligands, Photochemistry, Europium, Organometallic Compounds, Singlet state, Physical and Theoretical Chemistry, Terbium, Spectroscopy, Photons, Luminescent Agents, Photosensitizing Agents, Triazines, Ligand, Fluorescence, Energy Transfer, chemistry, Excited state, Luminescent Measurements |
| الوصف: | We have investigated, by means of steady-state and time-resolved optical spectroscopies, the excited-state dynamics of the luminescent europium complex Eu(III)(tta)(3)dpbt (tta = henoyltrifluoroacetonate; dbpt = 2-(N,N-diethylanilin-4-yl)-4,6-bis(3,5-dimethylpyrazol-1-yl)-1,3,5-triazine) with Gd(III)(tta)(3)dpbt and Tb(III)(tta)(3)dpbt as the reference complexes that cannot be photosensitized. In the Eu(III)(tta)(3)dpbt complex, the ligand dpbt exhibited biphasic fluorescence decay kinetics; the faster component (decay time constant, 8.5 ps) is ascribed to the rapid conversion of the lowest-lying singlet excited state of dpbt (S(1) or (1)dpbt*) to a ligand-to-metal charge transfer singlet state of the complex ((1)LMCT*), whereas the slower one (1.8 ns) is shown by temperature-dependent luminescence spectroscopy to be delayed fluorescence due to the LMCT-to-dpbt backward energy transfer and represents the time scale of efficient excitation energy flow from the (1)LMCT* state to the (5)D(1) state of Eu(III). On the basis of the spectroscopic results of the Ln(III)(tta)(3)dpbt complexes (Ln = Eu, Gd, and Tb), the crucial role of the (1)LMCT* state in photosensitization of the Eu(III)(tta)(3)dpbt complex is established, and a LMCT-mediated nontriplet sensitization mechanism is proposed, which is advantageous in high efficiency and low excitation photon energy as well as in low susceptibility against oxygen quenching. |
| تدمد: | 1520-5215 1089-5639 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c37965188f2e613a31ba1e49ddeca15a https://doi.org/10.1021/jp9103189 |
| رقم الأكسشن: | edsair.doi.dedup.....c37965188f2e613a31ba1e49ddeca15a |
| قاعدة البيانات: | OpenAIRE |
Find this issue from the American Chemical Society | تدمد: | 15205215 10895639 |
|---|