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تسجيل مستخدم جديدMicroED structure of Au146(p-MBA)57 at subatomic resolution reveals a twinned FCC cluster
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Sandra Vergara
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Solving the atomic structure of metallic clusters is fundamental to understanding their optical, electronic, and chemical properties. We report the structure of Au$_{text{146}}$(p-MBA)$_{text{57}}$ at subatomic resolution (0.85 {AA}) using electron diffraction (MicroED) and atomic resolution by X-ray diffraction. 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$_{2}$ 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$_{text{146}}$(p-MBA)$_{text{57}}$ is the largest cluster observed exhibiting a bulk-like FCC structure as well as the smallest gold particle exhibiting a stacking fault.
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