[Cu₁₃ {S₂ CNⁿ Bu₂ }₆ (acetylide)₄ ]⁺ : A Two-Electron Superatom

Area of Science:

• Inorganic Chemistry
• Materials Science
• Nanotechnology

Background:

• Copper nanoclusters are of interest for their unique electronic and catalytic properties.
• Understanding the structure-property relationship in copper clusters is crucial for designing new materials.
• Previous studies have explored smaller copper clusters, but a Cu13 cuboctahedral model remained elusive.

Purpose of the Study:

• To synthesize and structurally characterize a novel copper cluster with a Cu13 cuboctahedral core.
• To investigate the electronic properties of the synthesized Cu13 nanoclusters.
• To establish a model system for bulk copper's face-centered cubic (fcc) structure at the nanoscale.

Main Methods:

• Single-crystal X-ray diffraction for structural determination.
• Density Functional Theory (DFT) calculations for electronic structure analysis.
• Synthesis of [Cu13(S2CNnBu2)6(C≡CR)4](PF6) nanoclusters with R=C(O)OMe or C6H4F.

Main Results:

• The first structurally characterized Cu13 nanocluster with a cuboctahedral arrangement was synthesized.
• The cluster features a [Cu13]11+ core passivated by dithiolate and acetylide ligands.
• DFT calculations confirm the cluster's description as a two-electron superatom with a delocalized a1 HOMO, analogous to 1S jellium electrons.

Conclusions:

• The synthesized Cu13 nanoclusters serve as a nanoscale model for the bulk copper fcc structure.
• These findings demonstrate the potential of superatom chemistry in designing novel inorganic materials.
• The study provides insights into the electronic behavior of metal clusters and their ligand shells.