Competition of M−M vs M−X interactions via anion nature in the formation of mixed Au(I)/Ag(I) complexes

Investigation on the subtle differences and roles of ubiquitous polyatomic anions in the self-assembly of [Au(Spy)(PPh₂py)] with AgX (X^– = CF₃CO₂^–, CF₃SO₃^–, SbF₆^–, PF₆^–, and NO₃^–) has been carried out. The present results indicate both coexistence and competition of intracyclic Ag−Ag, intracyclic Ag−Au, intercyclic Au−Au, Ag⋅⋅⋅X, and Au⋅⋅⋅X interactions via both the polyatomic anions and a rhombic unit of [AuAgAuAg]. Four kinds of skeletal structures containing a [AuAgAuAg] unit form via the coordinating nature of polyatomic anions: a discrete structure with the Au/Ag−supported bidentate anion for CF₃CO₂^– and CF₃SO₃^–, a discrete structure with the Ag−monodentate anion for SbF₆^–, a 1D polymeric structure with both inter-rhombic Au−Au interaction and Ag−monodentate anion for PF₆^–, and a 1D polymeric structure with both inter-rhombic Au−Au interaction and an inter-rhombic Ag/Ag−bridged anion for NO₃^–.