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Reaction of 1,8-dilithionaphthalene with [AuCl(Et3P)] or [Au2Cl2(μ-dppm)] (dppm = bis(diphenylphosphinomethane)) in Et2O/THF leads to formation of bis(triethylphosphine)-1,8-diaurionaphthalene (1) and dppm-1,8-diaurionaphthalene (2), respectively. The dppm ligand present in complex 2bridges the two gold centers leading to formation of short intramolecular Au–Au distances of av. 2.85 . Complex 2reacts with AgPF6in THF/CH2Cl2to afford a dicationic Au4Ag2complex which has been isolated as the bis(hexafluorophosphate) salt (3). In this cluster, two molecules of 2sandwich two Ag cations resulting in the formation of a Au2AgAu2Ag six-membered ring in which the metal centers are connected by Au–Au (av. 2.84 ) and Au–Ag (av. 2.75 ) metallophilic interactions. This cluster is further stabilized by short Ag–C interactions involving some of the naphthalene carbon atoms. The luminescence spectra of 2and 3have been recorded. Both complexes display relatively broad emission bands centered at 540 nm which result, at least in part, from the heavy atom induced phosphorescence of the naphthalene chromophore. [ABSTRACT FROM AUTHOR]