Secondary ligand engineering of nanoclusters: Effects on molecular structures, supramolecular aggregates, and optical properties

Abstract

AbstractDeveloping new templates to evaluate the ligand engineering effect in manipulating nanoclusters from both molecular and supramolecular aspects remains highly desired in cluster science because it allows for an in‐depth understanding of structure‐property correlations. We herein presented the secondary ligand (i.e., the phosphine ligand) engineering based on an Ag29 nanocluster template and its dual effects on intracluster structures and intercluster aggregates. The “dissociation‐combination equilibrium” of phosphine ligands on the nanocluster surface was controlled by tailoring the C–H⋯π interactions within the ligand shell, which led to the fabrication of a family of [Ag29(BDT)12(PR3)x]3– nanoclusters. On the molecular level, the dissociation of phosphine ligands contracted the nanocluster framework, while the overall configuration of [Ag29(BDT)12]3– was retained. On the supramolecular level, the complete dissociation of phosphine ligands yielded a bare nanocluster, which followed a chiral crystallization mode, and its crystals displayed high optical activity, derived from circular dichroism and circularly polarized luminescence characterizations. Overall, this work presents the peripheral ligand effects in directionally controlling intracluster configurations and intercluster aggregations, which hopefully benefit future design and preparation of new nanoclusters or cluster‐based nanomaterials with customized structures and performances.