Controlling Gold Nanoclusters by Diphospine Ligands

We report the synthesis and structure determination of a new Au₂₂ nanocluster coordinated by six bidentate diphosphine ligands: 1,8-bis­(diphenyl­phosphino) octane (L⁸ for short). Single crystal X-ray crystallography and electrospray ionization mass spectrometry show that the cluster assembly is neutral and can be formulated as Au₂₂(L⁸)₆. The Au₂₂ core consists of two Au₁₁ units clipped together by four L⁸ ligands, while the additional two ligands coordinate to each Au₁₁ unit in a bidentate fashion. Eight gold atoms at the interface of the two Au₁₁ units are not coordinated by any ligands. Four short gold–gold distances (2.64–2.65 Å) are observed at the interface of the two Au₁₁ clusters as a result of the clamping force of the four clipping ligands and strong electronic interactions. The eight uncoordinated surface gold atoms in the Au₂₂(L⁸)₆ nanocluster are unprecedented in atom-precise gold nanoparticles and can be considered as potential <i>in situ</i> active sites for catalysis

Controlling Gold Nanoclusters by Diphospine Ligands

We report the synthesis and structure determination of a new Au₂₂ nanocluster coordinated by six bidentate diphosphine ligands: 1,8-bis­(diphenyl­phosphino) octane (L⁸ for short). Single crystal X-ray crystallography and electrospray ionization mass spectrometry show that the cluster assembly is neutral and can be formulated as Au₂₂(L⁸)₆. The Au₂₂ core consists of two Au₁₁ units clipped together by four L⁸ ligands, while the additional two ligands coordinate to each Au₁₁ unit in a bidentate fashion. Eight gold atoms at the interface of the two Au₁₁ units are not coordinated by any ligands. Four short gold–gold distances (2.64–2.65 Å) are observed at the interface of the two Au₁₁ clusters as a result of the clamping force of the four clipping ligands and strong electronic interactions. The eight uncoordinated surface gold atoms in the Au₂₂(L⁸)₆ nanocluster are unprecedented in atom-precise gold nanoparticles and can be considered as potential <i>in situ</i> active sites for catalysis