Comparative PCET study of a donor-acceptor pair linked by ionized and nonionized asymmetric hydrogen-bonded interfaces.
Comparative PCET study of a donor-acceptor pair linked by ionized and nonionized asymmetric hydrogen-bonded interfaces.
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DOI：
10.1021/ja809777j
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发表时间：
2009-06-10
影响因子：
15
通讯作者：
Nocera DG
中科院分区：
文献类型：
--
作者：
Young ER;Rosenthal J;Hodgkiss JM;Nocera DG
锌（II）卟啉-脒是萘二亚胺受体(A)的激发态电子供体(D)，其附羧酸盐或磺酸盐官能团。在酰胺和羧酸盐或磺酸盐之间形成的两点氢键（—[H+]—）建立了电荷转移的质子耦合电子转移（PCET）途径。两种D- [H+]- A组合的不同之处在于氢键界面内的质子构型。具体来说，amidinium将一个质子转移到羧酸盐上，形成非电离的脒-羧酸两点氢网络，而当与磺酸官能团结合时，amidinium保持两个质子，形成电离的脒-磺酸两点氢网络。因此，在二偶体内的这两种界面配置允许通过电离和非电离氢键界面并置的相同供体和受体的PCET动力学进行直接比较。从瞬态吸收光谱和瞬态发射光谱对PCET动力学的分析表明，电离界面受局部溶剂环境的影响更大，从而确定质子界面的初始静态构型是PCET动力学的关键决定因素。
A Zn(II) porphyrin-amidinium is the excited state electron donor (D) to a naphthalene diimide acceptor (A) appended with either a carboxylate or sulfonate functionality. The two-point hydrogen bond (---[H+]---) formed between the amidinium and carboxylate or sulfonate establishes a proton-coupled electron transfer (PCET) pathway for charge transfer. The two D---[H+]---A assemblies differ only by the proton configuration within the hydrogen bonding interface. Specifically, the amidinium transfers a proton to the carboxylate to form a non-ionized amidine-carboxylic acid two-point hydrogen network whereas the amidinium maintains both protons when bound to the sulfonate functionality forming an ionized amidinium-sulfonate two-point hydrogen network. These two interface configurations within the dyads thus allow for a direct comparison of PCET kinetics for the same donor and acceptor juxtaposed by an ionized and non-ionized hydrogen-bonded interface. Analysis of PCET kinetics ascertained from transient absorption and transient emission spectroscopy reveal that the ionized interface is more strongly impacted by the local solvent environment, thus establishing that the initial static configuration of the proton interface is a critical determinant to the kinetics of PCET.
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影响因子：
15
作者：
PRANATA, J;WIERSCHKE, SG;JORGENSEN, WL
通讯作者：
JORGENSEN, WL
影响因子：
15
作者：
Cape, JL;Bowman, MK;Kramer, DM
通讯作者：
Kramer, DM
影响因子：
2.9
作者：
Decornez, H;Hammes-Schiffer, S
通讯作者：
Hammes-Schiffer, S
影响因子：
--
作者：
Cukier, RI
通讯作者：
Cukier, RI
影响因子：
15
作者：
Galoppini, E;Fox, MA
通讯作者：
Fox, MA