Pincer-Ligand-Stabilized Group 10 Metal Nanoclusters: Chirality and Boat–Chair Structural Transformation

Atomically
precise metal nanoclusters bridge the gap between metal
atoms and metal nanoparticles, providing an ideal platform for correlating
the macroscopic properties of metal nanoparticles to their microstructures.
In comparison to the rapid development of coin metal nanoclusters,
the knowledge on group 10 metal nanoclusters is relatively limited
because of their active nature, resulting in the synthetic challenge.
In this work, we successfully synthesize three group 10 metal nanoclusters,
that is, Ni3(SNS)3, Ni3(SNOS)3, and Pd3(SNS)3, by using the SNS pincer
ligands, which well-stabilize the nickel and palladium metal kernels.
Intrinsic chirality of the nanoclusters that originated from the asymmetric
arrangement of the surface SNS pincer ligands is discovered. Oxidation-induced
irreversible transformation from boat-like Ni3(SNS)3 to chair-like Ni3(SNOS)3 is observed,
and the boat/chair structure-dependent reactivity is revealed. The
structural features and intriguing properties of Ni3 and
Pd3 nanoclusters stabilized by the pincer ligand will inspire
further research on group 10 metal nanoclusters.