Goldsmith Michael-Rock, George Christopher B, Zuber Gérard, Naaman Ron, Waldeck David H, Wipf Peter, Beratan David N
Department of Chemistry, Duke University, Durham, NC 27708, USA.
Phys Chem Chem Phys. 2006 Jan 7;8(1):63-7. doi: 10.1039/b511563a. Epub 2005 Nov 17.
Using a dissymmetrically-perturbed particle-in-a-box model, we demonstrate that the induced optical activity of chiral monolayer protected clusters, such as Whetten's Au28(SG)16 glutathione-passivated gold nanoclusters (J. Phys. Chem. B, 2000, 104, 2630-2641), could arise from symmetric metal cores perturbed by a dissymmetric or chiral field originating from the adsorbates. This finding implies that the electronic states of the nanocluster core are chiral, yet the lattice geometries of these cores need not be geometrically distorted by the chiral adsorbates. Based on simple chiral monolayer protected cluster models, we rationalize how the adsorption pattern of the tethering sulfur atoms has a substantial effect on the induced CD in the NIR spectral region, and we show how the chiral image charge produced in the core provides a convenient means of visualizing dissymmetric perturbations to the achiral gold nanocluster core.
使用非对称微扰的盒中粒子模型，我们证明了手性单层保护簇的诱导光学活性，例如惠滕的Au28(SG)16谷胱甘肽钝化金纳米簇（《物理化学杂志B》，2000年，104卷，2630 - 2641页），可能源于由吸附质产生的非对称或手性场微扰的对称金属核。这一发现意味着纳米簇核的电子态是手性的，但这些核的晶格几何形状无需被手性吸附质几何扭曲。基于简单的手性单层保护簇模型，我们阐明了连接硫原子的吸附模式如何对近红外光谱区域的诱导圆二色性产生重大影响，并且我们展示了在核中产生的手性镜像电荷如何为可视化非手性金纳米簇核的非对称微扰提供了一种便捷方式。
