Coherent wavepacket motion in an ultrafast electron transfer system monitored by femtosecond degenerate four-wave-mixing and pump-probe spectroscopy
Coherent wavepacket motion in an ultrafast electron transfer system monitored by femtosecond degenerate four-wave-mixing and pump-probe spectroscopy
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通过飞秒简并四波混合和泵浦探针光谱监测超快电子转移系统中的相干波包运动
作者：
Nagasawa;Y. ; Yoneda;Y. ; Nambu;S. ; Muramatsu;M. ; Takeuchi;E. ; Tsumori;H. ; Morikawa;S. ; Katayama;T. ; Miyasaka;H.
研究了两种光生放氢分子器件[（bpy）2 Ru（II）（phen-NHCO-bpy-R）Pt（II）Cl 2]2+（即，研究了[Ru（bpy）2（5-amino-phen）]2+与（4-carboxy-4′-R-bpy）PtCl 2（bpy = 2，2 ′-bipyridine，phen = 1，10-phen; RuPt-COOH（R = COOH），RuPt-CN（R = CN））的缩合产物。RuPt-CN表现出比RuPt-COOH更高的光催化性能，这是由于分子内光诱导电子转移（PET）的驱动力更大，与R的吸电子效应更强相关（RuPt-CN的ΔGPET = −0.43 eV，RuPt-COOH的Δ GPET = −0.16 eV）。这是第一次使用超快光谱对PET事件进行研究。相对于RuPt-COOH（3.1 × 109 s− 1），RuPt-CN（1.78 × 1010 s− 1）中PET的速率显著提高。对于每个系统，三种不同的构象产生三个不同的PET速率的存在下证明，这也与DFT结果进行了讨论。电荷分离态[（bpy）2 Ru（III）（phen-NHCO-bpy− stec-R）Pt（II）Cl 2]2+在亚皮秒时间范围内的形成和皮秒时间范围内的复合被表征。CS-态的形成被发现与还原猝灭的三重激发态的EDTA的双阴离子形式的离子对与双阳离子RuPt-COOH竞争。因此，关键中间体[（bpy）2 Ru（II）（phen-NHCO-bpy− stec-R）Pt（II）Cl 2]+（即，发现在H2形成之前，通过EDTA还原CS态或通过三重激发态的还原淬灭形成[（bpy）2 Ru（II）（phen-stec-NHCO-bpy-R）Pt（II）Cl 2]+来形成单电子还原物质。更重要的是，它也表明，在溶液中的构象的一些具有CS寿命足够长，以驱动从水中析氢。
The photoinduced electron transfer properties of two photo-hydrogen-evolving molecular devices (PHEMDs) [(bpy)2Ru(II)(phen-NHCO-bpy-R)Pt(II)Cl2]2+ (i.e., condensation products of [Ru(bpy)2(5-amino-phen)]2+ and (4-carboxy-4′-R-bpy)PtCl2; bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline; RuPt-COOH for R = COOH and RuPt-CN for R = CN) were investigated. RuPt-CN demonstrates higher photocatalytic performance relative to RuPt-COOH arising from a larger driving force for the intramolecular photoinduced electron transfer (PET) associated with a stronger electron-withdrawing effect of R (ΔGPET = −0.43 eV for RuPt-CN and −0.16 eV for RuPt-COOH). This is the first study on PET events using ultrafast spectroscopy. Dramatic enhancement is achieved in the rate of PET in RuPt-CN (1.78 × 1010 s−1) relative to RuPt-COOH (3.1 × 109 s−1). For each system, the presence of three different conformers giving rise to three different PET rates is evidenced, which are also discussed with the DFT results. Formation of a charge-separated (CS) state [(bpy)2Ru(III)(phen-NHCO-bpy−˙-R)Pt(II)Cl2]2+ in the sub-picosecond time regime and recombination in the picosecond time regime are characterized spectrophotometrically. The CS-state formation was found to compete with reductive quenching of the triplet excited state by EDTA whose dianionic form ion-pairs with dicationic RuPt-COOH. Thus, a key intermediate [(bpy)2Ru(II)(phen-NHCO-bpy−˙-R)Pt(II)Cl2]+ (i.e., the one-electron-reduced species) prior to the H2 formation was found to be formed either via reduction of the CS state by EDTA or via formation of [(bpy)2Ru(II)(phen−˙-NHCO-bpy-R)Pt(II)Cl2]+ by reductive quenching of the triplet excited state. More importantly, it is also shown that some of the conformers in solution possess a CS lifetime sufficiently long to drive hydrogen evolution from water.
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蓝铜蛋白的相干动力学和超快激发态弛豫；
DOI：
10.1039/b926518j
发表时间：
2010
期刊：
Physical chemistry chemical physics : PCCP
影响因子：
--
作者：
Y. Nagasawa;K. Fujita;Tetsuro Katayama;Y. Ishibashi;H. Miyasaka;T. Takabe;S. Nagao;S. Hirota
通讯作者：
S. Hirota
N,N-二甲基苯胺中恶嗪 1 系统超快电子转移动力学的非指数
影响因子：
2.9
作者：
S. Engleitner;M. Seel;W. Zinth
通讯作者：
W. Zinth
N,N-二甲基苯胺中恶嗪1体系的波包运动和超快电子转移
DOI：
--
发表时间：
1997
期刊：
影响因子：
--
作者：
M. Seel;S. Engleitner;W. Zinth
通讯作者：
W. Zinth
影响因子：
4.4
作者：
LAWLESS, MK;MATHIES, RA
通讯作者：
MATHIES, RA
影响因子：
--
作者：
KANDORI, H;KEMNITZ, K;YOSHIHARA, K
通讯作者：
YOSHIHARA, K