High-nuclearity and thiol protected core-shell [Cu75(S-Adm)32]2+: distorted octahedra fixed to Cu15 core via strong cuprophilic interactions

Atomically precise nanoclusters have a critical role in understanding the structure-property relationships at the atomic level. Copper nanoclusters have attracted considerable attention, but the synthesis is limited because of susceptibility to oxidation. Herein, we developed a reduction speed controlling method to synthesize [Cu-75(S-Adm)(32)](2+) (HS-Adm: 1-Adamantanethiol) nanocluster and reveal the key steps in the nucleation process. Cu-75 was first observed and characterized with the following features: (i) composed of a face-centered cubic Cu-15 kernel and a Cu-60 caged shell including 12 distorted octahedra. (ii) The observation of the shortest Cu-Cu bond (2.166(7) angstrom) in the Cu nanoclusters, which could result from the distortion of the octahedron. (iii) The sole mu(3)-S mode of S, which plays two roles as a vertex and bridge atom to connect Cu atoms. This work presents a unique nanoball Cu nanocluster with strong cuprophilic interaction and provides a novel method to expand the family of Cu nanoclusters as well.

Automated summary

By controlling the reduction speed, we synthesized a unique copper nanocluster with strong cuprophilic interaction and revealed the key steps in the nucleation process.