Photophysics of Ru(II) complexes with hydroxylated diimine ligands: Photoinduced electron/proton transfer to anthraquinone
Photophysics of Ru(II) complexes with hydroxylated diimine ligands: Photoinduced electron/proton transfer to anthraquinone
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Ru(II) 与羟基化二亚胺配体配合物的光物理学：光诱导电子/质子转移至蒽醌
DOI：
10.1016/j.poly.2021.115376
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发表时间：
2021
期刊：
影响因子：
2.6
通讯作者：
Schmehl, Russell H.
中科院分区：
文献类型：
--
作者：
Martinez, Kristina;Benson, Kaitlyn;Paul, Jared;Schmehl, Russell H.
本文报道了两种发光发色团[(bpy)2Ru(OHbpy)]2+和[(bpy)2Ru(OMebpy)]2+（bpy = 2,2 ' -联吡啶，OHbpy = 4-羟基-2,2 ' -联吡啶，OMebpy = 4-甲氧基-2,2 ' -联吡啶）与蒽醌（AQ）的3mlct激发态反应。为了确定光激发配合物与AQ之间潜在反应路径的自由能，我们进行了一系列的发光、电化学、分光光度和瞬态吸收研究。对于ombpy配合物，只有从3mlct态到AQ的激发态电子转移（ET*）是可能的。而对于OHbpy配合物，激发态可以通过激发态电子转移、ET*、激发态质子转移（PT*）和激发态质子耦合电子转移（PCET*）等多种途径与AQ发生反应。热力学分析表明，对于OHbpy配合物，PT*是非常吸氧的，不是一个可行的反应途径，而ET*和PCET*都可以发生。发光猝灭研究表明，OHbpy和ombpy激发配合物均与AQ发生反应（两者的kq~ 109M−1s−1）。瞬态吸收分析表明，对于ombpy配合物，没有光产物逃脱与猝灭反应相关的偶遇配合物。结果与3+/1-络合物的强静电缔合一致。对于OHbpy配合物的瞬态吸收结果清楚地表明PCET*产物是由偶遇配合物形成的。该结果代表了在偶遇络合物中通过质子耦合电子转移的发色团激发态反应的少数例子之一。
This manuscript reports the reaction of the3MLCT excited states of two luminescent chromophores, [(bpy)2Ru(OHbpy)]2+and [(bpy)2Ru(OMebpy)]2+(bpy = 2,2′-bipyridine, OHbpy = 4-hydroxy-2,2′-bipyridine, OMebpy = 4-methoxy-2,2′-bipyridine), with anthraquinone (AQ). A series of luminescence, electrochemical, spectrophotometric and transient absorption studies were done in order to determine free energies for the potential reaction paths between the photoexcited complexes and AQ. For the OMebpy complex, only excited state electron transfer (ET*) from the3MLCT state of the complex to AQ was possible. However, for the OHbpy complex, the excited state could react with AQ via a variety of pathways including excited state electron transfer, ET*, excited state proton transfer (PT*) and excited state proton coupled electron transfer (PCET*). The thermodynamic analysis revealed that, for the OHbpy complex PT* was very endergonic and not a viable reaction pathway, however both ET* and PCET* could occur. Luminescence quenching studies revealed that both the OHbpy and the OMebpy excited complexes reacted with AQ (kq~ 109M−1s−1for both). Transient absorption analysis showed that, for the OMebpy complex, no photoproducts escaped the encounter complex associated with the quenching reaction. The result is consistent with strong electrostatic association of the 3+/1- encounter complex. For the OHbpy complex transient absorption results clearly show the formation of PCET* products from the encounter complex. The result represents one of a small number of examples of excited states of chromophores reacting via proton coupled electron transfer within an encounter complex.
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用势 p Ka 图解码质子耦合电子转移：催化应用。
影响因子：
4.6
作者：
Eric S. Rountree;B. McCarthy;J. Dempsey
通讯作者：
J. Dempsey
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DOI：
10.1016/j.jphotochem.2020.112522
发表时间：
2020
期刊：
Journal of Photochemistry and Photobiology A: Chemistry
影响因子：
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作者：
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通讯作者：
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影响因子：
62.1
作者：
Warren, Jeffrey J.;Tronic, Tristan A.;Mayer, James M.
通讯作者：
Mayer, James M.
钌(IV)-氧配合物：三级磷配体的新用途
影响因子：
15
作者：
M. Marmion;K. Takeuchi
通讯作者：
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光诱导电子从激发的[三(2,2-联吡啶)钌(II)]2+转移到一系列具有小正或负吉布斯反应能和负活化焓的蒽醌。
DOI：
--
发表时间：
1999
期刊：
影响因子：
--
作者：
R. Frank;G. Greiner;H. Rau
通讯作者：
H. Rau