An unprecedented luminescent polynuclear gold(I) μ(3)-sulfido cluster with a thiacrown-like architecture.

An unprecedented Au(18) thiacrown directed by Au(I)···Au(I) interactions and supported by tridentate phosphine (dpepp) and μ(3)-sulfido ligands that highly resembles the 18-membered thiacrown ether [18]aneS(6) in appearance has been synthesized. The sulfides of the Au(3)(μ(3)-S) units in the central cavity point toward each other and are located on the same plane, allowing them to bind the soft Ag(+) ion with immediate and pronounced spectroscopic changes. Reversible binding and spectroscopic changes can be readily achieved upon addition of CH(3)CN without disruption of the Au(18) macrocycle.