A giant Dy${}_{76}$ cluster: A fused bi-nanopillar structural model for lanthanide clusters

Although great achievements have been made in the synthesis of giant lanthanide clusters, novel structural models are still scarce. Herein, we report a giant lanthanide cluster Dy${}_{76}$, constructed from [Dy${}_3$(μ${}_3$-OH)${}_4$] and [Dy${}_5$(μ${}_4$-O)(μ${}_3$-OH)${}_8$] building blocks. As the largest known Dy cluster, the structure of Dy${}_{76}$ can be seen as arising from the fusion of two Dy${}_{48}$ clusters; these clusters can be isolated under various synthetic conditions and were characterized by single-crystal X-ray diffraction. This new, fused structural model of the pillar motif has not been found in Ln clusters. Furthermore, the successful conversion of Dy${}_{76}$ back into Dy${}_{48}$ in a retrosynthetic manner supports the proposed fusion formation mechanism of Dy${}_{76}$. Electrospray ionization mass spectrometry (ESI-MS) analysis suggests that the metal cluster skeleton of Dy${}_{76}$ shows good stability in various solvents. This work not only reveals a new structural type of Ln clusters but also provides insight into the novel fusion assembly process. (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)