Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.
Department of Theoretical and Computational Molecular Science, Institute for Molecular Science , Myodaiji, Okazaki 444-8585, Japan.
J Am Chem Soc. 2016 Mar 30;138(12):3950-3. doi: 10.1021/jacs.5b12747. Epub 2016 Mar 2.
Revealing the size-dependent periodicities (including formula, growth pattern, and property evolution) is an important task in metal nanocluster research. However, investigation on this major issue has been complicated, as the size change is often accompanied by a structural change. Herein, with the successful determination of the Au44(TBBT)28 structure, where TBBT = 4-tert-butylbenzenethiolate, the missing size in the family of Au28(TBBT)20, Au36(TBBT)24, and Au52(TBBT)32 nanoclusters is filled, and a neat "magic series" with a unified formula of Au8n+4(TBBT)4n+8 (n = 3-6) is identified. Such a periodicity in magic numbers is a reflection of the uniform anisotropic growth patterns in this magic series, and the n value is correlated with the number of (001) layers in the face-centered cubic lattice. The size-dependent quantum confinement nature of this magic series is further understood by empirical scaling law, classical "particle in a box" model, and the density functional theory calculations.
揭示尺寸依赖性的周期性（包括公式、生长模式和性能演化）是金属纳米团簇研究中的一项重要任务。然而，由于尺寸变化通常伴随着结构变化，因此对这一主要问题的研究变得复杂。在此，通过成功确定 Au44(TBBT)28 的结构，其中 TBBT = 4-叔丁基苯硫酚，填补了 Au28(TBBT)20、Au36(TBBT)24 和 Au52(TBBT)32 纳米团簇家族中缺失的尺寸，形成了一个整洁的“幻数系列”，具有统一的 Au8n+4(TBBT)4n+8 公式（n = 3-6）。这种幻数周期性反映了该幻数系列中均匀各向异性的生长模式，n 值与面心立方晶格中（001）层的数量相关。通过经验标度定律、经典“箱中粒子”模型和密度泛函理论计算，进一步理解了该幻数系列的尺寸相关量子限制性质。
