Photophysics of Oligothiophenes End‐Capped with Platinum(II) Auxochromes
Photophysics of Oligothiophenes End‐Capped with Platinum(II) Auxochromes
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低聚噻吩末端的光物理学——用铂 (II) 助色剂封端
DOI：
10.1002/cptc.202000123
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发表时间：
2020
期刊：
影响因子：
3.7
通讯作者：
Schanze, Kirk S.
中科院分区：
文献类型：
--
作者：
Gundogan, Ali S.;Jagadesan, Pradeepkumar;Schanze, Kirk S.
合成了一系列两端均带有−铂(Bu3)2Cl型端基的四种低聚硫杂环化合物，并研究了它们的激发态性质。观察到低聚物的低荧光量子产率(<；2 %)，表明铂对系间交叉效率有很强的影响。没有检测到任何低聚物的磷光；然而，通过纳秒瞬变光谱观察到含有一个以上噻吩基的低聚物有很强的三重-三重吸收。由于铂原子诱导了较大的自旋-轨道耦合，低聚物表现出较短的三重态寿命(∼1-2 μS)。通过测量单线态氧量子产额，间接确定了ISC产额的下限。飞秒-皮秒瞬时吸收研究表明，在1012s-1010s−1范围内，ISC速率随齐聚物长度的增加而减小。电化学研究表明，低聚物具有较低的氧化电位(约0.1 V vs.Fc/Fc+)。在甲基紫精存在下，低聚物的三重态吸收猝灭，同时在纳秒暂态光谱中相应的阳离子自由基吸收带上升，证实了电子转移是从它们的三重态发生的。
A series of four oligothiophenes end‐capped with −Pt(PBu3)2Cl moieties on both ends of the oligomers was synthesized, and their excited state properties were investigated. The observation of low fluorescence quantum yield (<2 %) for the oligomers indicates the strong effect of platinum on the intersystem crossing (ISC) efficiency. No phosphorescence was detected for any of the oligomers; however, strong triplet‐triplet absorption was observed by nanosecond transient spectroscopy for oligomers with more than one thiophene unit. The oligomers displayed short triplet lifetimes (∼1–2 μs) compared to the unmetallated oligomers, due to large spin‐orbit coupling induced by the platinum atom. The lower limits of the ISC yields were indirectly determined by measuring the singlet oxygen quantum yields. Femtosecond–picosecond transient absorption studies revealed that the ISC rate ranges from 1012–1010s−1, decreasing with increasing oligomer length. Electrochemical studies showed that the oligomers exhibit relatively low oxidation potentials (ca. 0.1 V vs. Fc/Fc+). Quenching of the oligomers’ triplet state absorption, simultaneously with the rise of their corresponding cationic radical absorption band in nanosecond transient spectra in the presence of methyl viologen, as an electron acceptor, established that the electron transfer occurs from their triplet state.
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影响因子：
2.3
作者：
Sonae Kotani;K. Shiina;K. Sonogashira
通讯作者：
Sonae Kotani;K. Shiina;K. Sonogashira
DOI：
--
发表时间：
2000
期刊：
影响因子：
--
作者：
J. Yang;W. Paa;M. Hotzel;S. Rentsch
通讯作者：
S. Rentsch
影响因子：
2.9
作者：
D. Lap;D. Grebner;S. Rentsch
通讯作者：
D. Lap;D. Grebner;S. Rentsch
影响因子：
1.8
作者：
BECKER, RS;DEMELO, JS;ELISEI, F
通讯作者：
ELISEI, F
DOI：
--
发表时间：
1999
期刊：
影响因子：
--
作者：
G. Wegmann;R. Mahrt;H. Bässler;H. Giessen;M. Murgia;O. Kapousta;M. Muccini;C. Taliani;R. Zamboni
通讯作者：
R. Zamboni