Self-assembly of luminescent Zn–Ln (Ln = Sm and Nd) nanoclusters with a long-chain Schiff base ligand

Abstract

Two 12-metal Zn–Ln nanoclusters [Zn₈Ln₄L₈(OAc)₈](OH)₄ (Ln = Sm (1) and Nd (2)) were prepared using a long-chain Schiff base ligand with a flexible (CH₂)₃O(CH₂)₂O(CH₂)₃ backbone. These two Zn–Ln clusters possess interesting rectangular structures. The long-chain Schiff base ligand adopts a “linear” configuration in the structures, resulting in the large sizes of 1 and 2 (about 9 × 19 × 28 Å). Chromogenic Zn/L components in the clusters can act as efficient sensitizers for lanthanide luminescence, and 1 and 2 exhibit emission from Sm³⁺ and Nd³⁺, respectively. Their visible and NIR luminescence properties were investigated.