Time-resolved monitoring of dynamic self-assembly of Au(i)-thiolate coordination polymers

Abstract

Research interest in dynamic assemblies of coordination polymers (CPs) has been rising in recent years for the similarity with life systems in their self-adaptable morphologies and properties. However, monitoring of the assembly process and elucidating the nature for the morphological transformation are very challenging. Here, UV-Vis spectroscopy has been explored as a time-resolved method for monitoring the self-assembly of Au(I)–thiolate CPs in situ. Both step-wise and synergetic effects of the weak interactions in Au(I)–3-mercaptopropionic acid (MPA) CPs, such as H-bonding, coordination bonding, Au(I)–Au(I) interactions and static interactions have been found from the spectral fingerprints, which elucidated the driving forces for the unique morphological transformations from strings to lamellar structures. This work represents a breakthrough in that dynamic self-assembly behaviours can be explained by molecular interactions from molecular level evidences. Based on the spectral fingerprint–structure relationship the reversible and dynamic assembly of Au(I)–MPA CPs can be easily probed.