Department of Chemistry, KU Leuven , Celestijnenlaan 200D, 3001 Leuven, Belgium.
J Am Chem Soc. 2017 Oct 25;139(42):14853-14856. doi: 10.1021/jacs.7b08338. Epub 2017 Oct 16.
Monolayer-protected metal clusters (MPCs) have recently gained significant research interest, since they are promising candidates for various applications in bioimaging and catalysis. Besides this, MPCs promise to aid in understanding the evolution of the metallic state from bottom-up principles. MPCs can be prepared with atomic precision, and their nonscalable properties (indicating molecule-like behavior) have been studied with a variety of techniques both theoretically and experimentally. Here, we present spectrally resolved second-order nonlinear optical scattering experiments on thiolate-protected gold clusters (Au(SR), Au(SR), and Au(SR)). The three clusters share common resonance enhancement around 490 nm, which is ascribed to an interband transition. This indicates emerging metal-like properties, and we tentatively assign the onset of metal-like behavior somewhere between 102 and 130 gold atoms.
单层保护金属簇（MPC）最近引起了广泛的研究兴趣，因为它们在生物成像和催化等各个领域具有广阔的应用前景。此外，MPC 有望帮助我们从底层原理理解金属态的演变。MPC 可以通过原子精度制备，并且它们的非扩展性（表明分子样行为）已经通过各种理论和实验技术进行了研究。在这里，我们介绍了对硫醇保护的金簇（Au(SR)、Au(SR)和 Au(SR)）进行的光谱分辨二阶非线性光学散射实验。这三个簇在 490nm 附近具有共同的共振增强，这归因于带间跃迁。这表明出现了类金属性质，我们初步将类金属行为的开始归因于 102 到 130 个金原子之间。
