Structured copper-hydride nanoclusters provide insight into the surface-vacancy-defect to non-defect structural evolution.

Exploring the structural evolution of clusters with similar sizes and atom numbers induced by the removal or addition of a few atoms contributes to a deep understanding of structure-property relationships. Herein, three well-characterized copper-hydride nanoclusters that provide insight into the surface-vacancy-defect to non-defect structural evolution were reported. A surface-defective copper hydride nanocluster [Cu 28 (S- c -C 6 H 11 ) 18 (PPh 2 Py) 3 H 8 ] 2+ (Cu 28 -PPh 2 Py for short) with only one C 1 symmetry axis was synthesized using a one-pot method under mild conditions, and its structure was determined. Through ligand regulation, a 29 th copper atom was inserted into the surface vacancy site to give two non-defective copper hydride nanoclusters, namely [Cu 29 (SAdm) 15 Cl 3 (P(Ph-Cl) 3 ) 4 H 10 ] + (Cu 29 -P(Ph-Cl) 3 for short) with one C 3 symmetry axis and (Cu 29 (S- c -C 6 H 11 ) 18 (P(Ph- p Me) 3 ) 4 H 10 ) + (Cu 29 -P(Ph-Me) 3 for short) with four C 3 symmetry axes. The optimized structures show that the 10 hydrides cap four triangular and all six square-planar structures of the cuboctahedral Cu 13 core of Cu 29 -P(Ph-Me) 3 , while the 10 hydrides cap four triangular and six square-planar structures of the anti-cuboctahedral Cu 13 core of Cu 29 -P(Ph-Cl) 3 , with the eight hydrides in Cu 28 -PPh 2 Py capping four triangular and four square planar-structures of its anti-cuboctahedral Cu 13 core. Cluster stability was found to increase sequentially from Cu 28 -PPh 2 Py to Cu 29 -P(Ph-Cl) 3 and then to Cu 29 -P(Ph-Me) 3 , which indicates that stability is affected by the overall structure of the cluster. Structural adjustments to the metal core, shell, and core-shell bonding model, in moving from Cu 28 -PPh 2 Py to Cu 29 -P(Ph-Cl) 3 and then to Cu 29 -P(Ph-Me) 3 , enable the structural evolution and mechanism responsible for their physicochemical properties to be understood and provide valuable insight into the structures of surface vacancies in copper nanoclusters and structure-property relationships.