Steady-State and Picosecond Spectroscopy of Li+ or Ca2+ Complexes with a Crowned Merocyanine. Reversible Photorelease of Cations
Steady-State and Picosecond Spectroscopy of Li+ or Ca2+ Complexes with a Crowned Merocyanine. Reversible Photorelease of Cations
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Li 或 Ca2 与冠部花青配合物的稳态和皮秒光谱。
DOI：
10.1021/jp952783u
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
B. Valeur
中科院分区：
文献类型：
--
作者：
Monique M. Martin;Andreia Plaza;Y. Meyer;F. Badaoui;J. Bourson;Andre Lefevre;B. Valeur
用稳态和时间分辨光谱研究了汞染料DCM（4-（dicyanmethylene）-2-methyl-6-（p-（dimethylamino）styryl）-4H-pyran）的冠醚衍生物与Li+和Ca~（2+）的络合物在乙腈中的可逆光释放。通过荧光光谱法获得的结果揭示了在含有DCM −冠醚络合物的溶液中存在两种发射物质。一个物种与2 ns的寿命是由于从阳离子光释放产生的自由配体，与最大形成产率为86%的Li+和41%的Ca 2+。另一个与400 ps轻微蓝移发射的两种阳离子建议是由于松散的复杂。用0.7ps的425nm脉冲激发后2ns内的瞬态吸收和增益谱研究了阳离子光释放的机理。在360 - 660 nm光谱范围内，观察到的主要变化发生在30 ps内。对于较长的时间延迟的时间分辨差分光谱表明占主导地位的衰减1…
Reversible photorelease of Li+ and Ca2+ cations from complexes with a crowned derivative of the merocyanine dye DCM (4-(dicyanomethylene)-2-methyl-6-(p-(dimethylamino)styryl)-4H-pyran) in acetonitrile is investigated by steady-state and time-resolved spectroscopy. The results obtained by fluorescence spectroscopy reveal the presence of two emitting species in solutions containing DCM−crown complexes. One species with a 2 ns lifetime is attributed to the free ligand resulting from cation photorelease, with a maximum formation yield of 86% for Li+ and 41% for Ca2+. The other one with a 400 ps slightly blue-shifted emission for both cations is suggested to be due to a loose complex. The mechanism of cation photorelease is studied by transient absorption and gain spectroscopy within 2 ns after excitation with a 0.7 ps pulse at 425 nm. In the 360−660 nm spectral range, the main changes observed take place within 30 ps. For longer time delays the time-resolved differential spectra indicate a dominant decay of 1...