Supramolecular Au(I) systems with luminescent properties. Aggregation studies

Abstract

Gold(I) organometallic compounds display electronic properties that make them suitable candidates for constituting supramolecular aggregates and presenting absorption and emission of ultraviolet-visible radiation. The present research project describes the synthesis of two gold(I) organometallic compounds where the metallic centre is coordinated to a pyridine-type ligand bonded to a polyethylene glycol (PEG) structure, as well as alkynyl ligands bonded to chromophore groups (aniline or coumarin). Aggregation of one of the synthetized compounds dissolved in acetonitrile and acetonitrile / water mixtures in variable proportions has been studied. By means of ultraviolet-visible absorption and emission measurements, some indicators of aggregation have been found. In addition, in this project there is a study of how aggregation is affected by the solute concentration and the relative content of water in the solvent. Finally, SAXS (small angle X-ray scattering) experiments and optical microscopy observations have been performed to obtain more experimental evidences of the presence of supramolecular aggregates in the solutions from the studied compound. The scope of the research included to analyse their sizes, shapes and aggregation morphologies