Deciphering icosahedra structural evolution with atomically precise silver nanoclusters

Determining the atomic structure of nanoparticles (NPs) is critical for understanding their structural evolution and properties. However, controlling the growth of multiply-twinned metal NPs remains challenging because of numerous competing pathways. In this work, we report the synthesis of two giant silver icosahedral nanoclusters, [Ag213(C≡CR1)96]5- and [Ag429Cl24(C≡CR2)150]5- (Ag213 and Ag429, R1 =3,4,5-F3C6H2 and R2 = 4-CF3C6H4), achieved through ligand engineering and kinetic control. Single-crystal x-ray diffraction reveals that Ag213 and Ag429 have multilayered icosahedral Ag141 |(Ag13@Ag42@Ag86) and Ag297 (Ag13@Ag42@Ag92@Ag150) cores, respectively. Notably, Ag429 with 260 valence electrons is the largest Ag0-containing nanocluster reported to date. These two giant silver nanoclusters are metallic in nature, as confirmed by their plasmonic absorption and pump-power-dependent excited-state dynamics. Their atomically precise structures support the layer-by-layer evolution from nuclei to seeds of silver icosahedra.