Tuning the luminescent properties of a Ag/Au tetranuclear complex featuring metallophilic interactions via solvent-dependent structural isomerization

In this paper the reaction products of the basic gold(I) species [Au(CCl)] against the acid salt Ag(OClO) in the presence of the S-donor macrocyclic ligand 1,4,7-trithiacyclononane ([9]aneS) are studied in different solvents. Two different isomers of stoichiometry [{Au(CCl)}Ag([9]aneS)] were isolated depending on the solvent used, dichloromethane or tetrahydrofuran, which show different luminescence in the solid state. X-ray diffraction studies of these compounds reveals that both show the same heteropolynuclear Ag···Au···Au···Ag system but with different Au···Au interaction distances and different relative positions of the cationic fragment [Ag([9]aneS)] in the structure with respect the bimetallic Au···Au core. This work includes a study of the optical properties of both isomers, as well as time-dependent density functional theory calculations that were performed to determine the origin of their different luminescence.D.G.I. MINECO/FEDER (Project Nos. CTQ2016-75816-C2-2-P and CTQ2016-75816-C2-1-P) is acknowledged for financial support. V.L. thanks Fondazione Banco di Sardegna for financial support. R.D. also acknowledges CAR for an FPI grant.Peer Reviewe