Vergara Sandra, Lukes Dylan A, Martynowycz Michael W, Santiago Ulises, Plascencia-Villa Germán, Weiss Simon C, de la Cruz M Jason, Black David M, Alvarez Marcos M, López-Lozano Xochitl, Barnes Christopher O, Lin Guowu, Weissker Hans-Christian, Whetten Robert L, Gonen Tamir, Yacaman Miguel Jose, Calero Guillermo
Department of Physics and Astronomy, The University of Texas at San Antonio , San Antonio, Texas 78249, United States.
Department of Structural Biology, University of Pittsburgh , Pittsburgh, Pennsylvania 15260, United States.
J Phys Chem Lett. 2017 Nov 16;8(22):5523-5530. doi: 10.1021/acs.jpclett.7b02621. Epub 2017 Oct 31.
Solving the atomic structure of metallic clusters is fundamental to understanding their optical, electronic, and chemical properties. Herein we present the structure of the largest aqueous gold cluster, Au(p-MBA) (p-MBA: para-mercaptobenzoic acid), solved by electron micro-diffraction (MicroED) to subatomic resolution (0.85 Å) and by X-ray diffraction at atomic resolution (1.3 Å). The 146 gold atoms may be decomposed into two constituent sets consisting of 119 core and 27 peripheral atoms. The core atoms are organized in a twinned FCC structure, whereas the surface gold atoms follow a C rotational symmetry about an axis bisecting the twinning plane. The protective layer of 57 p-MBAs fully encloses the cluster and comprises bridging, monomeric, and dimeric staple motifs. Au(p-MBA) is the largest cluster observed exhibiting a bulk-like FCC structure as well as the smallest gold particle exhibiting a stacking fault.
解析金属团簇的原子结构对于理解其光学、电子和化学性质至关重要。在此，我们展示了最大的水相金团簇Au(p-MBA)（p-MBA：对巯基苯甲酸）的结构，该结构通过电子微衍射（MicroED）解析至亚原子分辨率（0.85 Å），并通过X射线衍射解析至原子分辨率（1.3 Å）。146个金原子可分解为两个组成部分，分别由119个核心原子和27个外围原子组成。核心原子以孪晶面心立方（FCC）结构排列，而表面金原子围绕平分孪晶面的轴呈C旋转对称性。57个p-MBA的保护层完全包裹团簇，并包含桥连、单体和二聚体主链基序。Au(p-MBA)是观察到的具有类体相FCC结构的最大团簇，也是具有堆垛层错的最小金颗粒。
