Design of luminescent sulfur-containing polynuclear gold(I) complexes for advanced nanomaterials and chemosensors

Abstract

A series of high-nuclearity gold(I) sulfido complexes with bridging diphosphine ligands have been synthesized and isolated, with the general formulae of [Au10(μ-P∧P)4(μ3-S) 4]X2 and [Au12(μ-P∧P) 6(μ3-S)4]X4 (P∧P = diphosphine; X = PF6 or ClO4). Intense green and orange emissions were observed upon excitation at λ > 350 nm both in the solid state and in solutions. The green emission has been attributed to originate from excited states derived from the metal-perturbed intraligand (IL) transition while the orange emission arises from the ligand-to-metal-metal bond charge-transfer (LMMCT; S (Au⋯Au) states. The switching on and off of the LMMCT emission in a series of dinuclear gold(I) thiolate complexes with crown ether pendants induced by ion-binding has been demonstrated, and this provides a new strategy for the design of luminescence signalling and chemosensing devices in optoelectronics and sensor technology.