External heavy-atom effect of gold in a supramolecular acid–base π stack
Abstract
The nucleophilic trinuclear Au(I) ring complex Au3(p-tolNCOEt)3, 1, forms a sandwich adduct with the organic Lewis acid
COEt)3
π-base molecules alternate with the octafluoronaphthalene π-acid molecules with distances between the centroid of
COEt)3, which is related to inter-ring Au–Au bonding, and leads to the appearance of a bright yellow emission band observed at room temperature. The structured profile, the energy, and the lifetime indicate that the yellow emission of the 1·C10F8 adduct is due to monomer phosphorescence of the octafluoronaphthalene. The 3.5 ms lifetime of the yellow emission of 1·C10F8 is two orders of magnitude shorter than the lifetime of the octafluoronaphthalene phosphorescence, thus indicating a strong gold heavy-atom effect. The diffuse-