[Cu₁₃{S₂CN^<i>n</i>Bu₂}₆(acetylide)₄]⁺: A Two‐Electron Superatom

Abstract

The first structurally characterized copper cluster with a Cu₁₃ centered cuboctahedral arrangement, a model of the bulk copper fcc structure, was observed in [Cu₁₃ (S₂ CNⁿ Bu₂ )₆ (C≡CR)₄ ](PF₆ ) (R=C(O)OMe, C₆ H₄ F) nanoclusters. Four of the eight triangular faces of the cuboctahedron are capped by acetylide groups in μ₃ fashion, and each of the six square faces is bridged by a dithiolate ligand in μ₂ ,μ₂ fashion, which leads to a truncated tetrahedron of twelve sulfur atoms. DFT calculations are fully consistent with the description of these Cu₁₃ clusters as two-electron superatoms, that is, a [Cu₁₃ ]¹¹⁺ core passivated by ten monoanionic ligands, with an a₁ HOMO containing two 1S jellium electrons.