Multiple evidence for gold(I)-siher(I) interactions in solution

[AuAg³(C₆F₅)(CF₃CO ₂)₃ (CH₂PPh₃)Jn (2) was prepared by reaction of [Au(C₆F₅)(CH₂PPh₃)] (1) and [Ag(CF₃CO₂)] (1:3). The crystal structures of complexes 1 and 2 were determined by X-ray diffraction, and the latter shows a polymeric 2D arrangement built by Au-Ag, Ag-Ag, and Ag-O contacts. The metallophilic interactions observed in 2 in the solid state seem to be preserved in concentrated THF solutions, as suggested by EXAFS, pulsed-gradient spin-echo NMR, and photophysical studies, which showed that the structural motif [AuAg₃(C₆F₅)(CF₃CO₂) ₃(CH₂PPh₃)] is maintained under such conditions. Time-dependent DFT calculations agree with the experimental photophysical energies and suggest a metalto-ligand charge-transfer phosphorescence process. Ab initio calculations give an e timated interaction energy of around 60 kJ mol^-1 for each Au-Ag interaction.