Au147(SPh)30(PPh3)12: A Geometrically Closed, but Electronically Open Triple-Shell Icosahedral Gold Cluster and its Geometrically Open Counterpart

Angew Chem Int Ed Engl. 2025 Jun 24;64(26):e202500586. doi: 10.1002/anie.202500586. Epub 2025 May 16.

Abstract

The aesthetic platonic solids have been known since ancient times, and the structure of all five platonic solids is also found in chemical compounds. While gold sub-nanometer clusters and gold nanoparticles with an icosahedral structure have been known for a long time to exist, a multi-shell icosahedral gold cluster at the intermediate size between 13 and thousands of atoms has been elusive. Here we present the synthesis and crystallographic characterization of the first triple-shell icosahedral metal cluster, Au147(SPh)30(PPh3)12 1. The gold core in 1 is stabilized by phosphines and thiolates, but surprisingly no staple motifs are formed. A second cluster, Au146(SPh)30(PPh3)12 2, cocrystallizes and is identified as having a closed electronic shell but can be considered as a geometrically open pendant of 1. The unique clusters are characterized experimentally by EDX, UV/vis, DLS, and EPR and theoretically by quantum chemical calculations.

Keywords: Crystal structure; DFT‐calculations; EPR; Icosahedron; Metal cluster.