Aggregation-Mediated Cuprophilic Interactions Governing the Luminescence of a Cu ₆ Nanocluster

Cuprophilic interactions are increasingly recognized as key determinants in the design of functional assemblies, particularly for enhancing luminescence. However, achieving precise control of cuprophilic interactions in self-assembled, atomically precise copper nanoclusters remains challenging. Here, we present a straightforward strategy to systematically modulate cuprophilic interactions through the supramolecular self-assembly of an atomically precise Cu(I) nanocluster, [Cu6(MBID)6] (Cu6, HMBID = 2-mercaptobenzimidazole). The aggregation behavior of Cu6 is finely regulated by solvation engineering, with controlled self-assembly into well-defined hexagonal nanoplates occurring exclusively within a solvent fraction range (fw = 50–60%). This process strengthens cuprophilic interactions, thereby leading to pronounced improvements in photoelectrical properties, including luminescence and photocurrent generation. Ab initio molecular dynamics (AIMD) simulations reveal that in a 50:50 water/DMSO medium, Cu···Cu distances within Cu6 are significantly shortened, providing computational evidence for strengthened metallophilic interactions during aggregation. Complementarily, Raman spectroscopy directly tracks the evolution of Cu···Cu distances across distinct aggregation states, offering experimental confirmation of aggregation-induced reinforcement of cuprophilic interactions. Collectively, this work establishes Cu6 as a robust model for supramolecular cluster self-assembly and underscores the pivotal role of metallophilic interactions in constructing cluster-based aggregates with tunable optical properties.