Chiroptical Responses of d-/l-Penicillamine-Capped Gold Clusters under Perturbations of Temperature Change and Phase Transfer
Chiroptical Responses of d-/l-Penicillamine-Capped Gold Clusters under Perturbations of Temperature Change and Phase Transfer
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DOI：
10.1021/jp074830b
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发表时间：
2007-09
影响因子：
3.7
通讯作者：
H. Yao;Toshiyuki Fukui;K. Kimura
中科院分区：
文献类型：
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作者：
H. Yao;Toshiyuki Fukui;K. Kimura
我们报告的手性光学性质的光学活性的d-/l-青霉胺封端的金簇作为温度或分散相的函数。通过凝胶电泳对检测的簇进行尺寸选择。通过小角X射线散射（SAXS）分析确定的金簇（核心直径为0.57 nm）的圆二色性（CD）信号实际上是温度依赖性的（20和40 °C），而普通的吸收光谱几乎与温度无关。此外，金簇（0.57 nm）从水到甲苯的相转移成功地实现了疏水化，使用四辛基铵阳离子和表面青霉胺分子中的羧酸根阴离子之间的离子缔合。在金属基电子跃迁区，被d-或l-对映体覆盖的相转移团簇仍然显示出强烈的光学活性，具有相反的符号（镜像关系）。在相转移时，我们发现轮廓发生了显著变化...
We report chiroptical properties of optically active d-/l-penicillamine-capped gold clusters as a function of temperature or dispersion phase. The clusters examined are size-selected via gel electrophoresis. Circular dichroism (CD) signals of the gold clusters (0.57 nm in the core diameter), whose sizes have been determined by a small-angle X-ray scattering (SAXS) analysis, are practically temperature-dependent (20 and 40 °C), whereas ordinary absorption spectra are almost independent of the temperature. Furthermore, phase transfer of the gold clusters (0.57 nm) from water to toluene is successfully achieved by hydrophobization using ion association between tetraoctylammonium cations and carboxylate anions in surface penicillamine molecules. The phase-transferred clusters covered with d- or l-enantiomer still display intense optical activity with the opposite sign (mirror-image relationship) in the metal-based electronic transition region. Upon phase transfer, we find a significant change in the profiles ...