[Ag-48(C (CBu)-Bu-t)(20)(CrO4)(7)]: An Atomically Precise Silver Nanocluster Co-protected by Inorganic and Organic Ligands

Zhang S., Alkan F. , Su H., Aikens C. M. , Tung C., Sun D.

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, vol.141, no.10, pp.4460-4467, 2019 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 141 Issue: 10
  • Publication Date: 2019
  • Doi Number: 10.1021/jacs.9b00703
  • Page Numbers: pp.4460-4467


The elaborate selection of capping ligands is of great importance in the synthesis of atomically precise metal nanoclusters. Organic thiolates, alkynyls, phosphines, and/or their combinations are the ligands most widely utilized to protect metal nanoclusters, while inorganic oxo anions have been almost neglected in this field. Herein, the first CrO42-/(BuC)-Bu-t C- co-capped Ag-48 nanocluster (SD/Ag48, SD = SunDi) was synthesized and structurally characterized by single-crystal X-ray diffraction. The pseudo-5-fold symmetric metal skeleton of SD/Ag48 shows a core shell structure composed of a Ag-23 cylinder encircled by an outer Ag-25 shell. Unprecedentedly, coexistence of inorganic (CrO42-) and organic ((BuC)-Bu-t C-) ligands was observed on the surface of SD/Ag48. The inorganic CrO42- anion plays three important roles in the construction of silver nanoclusters: (i) passivating the Ag-23 kernel; (ii) connecting the core and shell; and (iii) protecting the Ag-25 shell. This nanocluster belongs to a 14e superatom system and exhibits successive molecule-like absorption bands from the visible to the ultraviolet region. This work not only establishes a fresh inorganic ligand strategy in the synthesis of silver nanoclusters but also provides a new insight into the important surface coordination chemistry of CrO42- in the shape control of silver nanoclusters.