Gui-Xin Yan, Er-Xia Chen, Jin-Xia Yang, Jian Zhang*, Qipu Lin*

Cite this article: Chin. J. Struct. Chem., 2025, 44(12), 100759. DOI: 10.1016/j.cjsc.2025.100759

Publication date: December 1, 2025

Keywords: Heterometallic oxo clusters; Organotin clusters; Chirality; Circularly polarized luminescence; Dual emission

ABSTRACT

Chiral metal-organic clusters (MOCs) integrating lanthanide ions (Ln3+) and organic luminophores present a promising platform for modulating circularly polarized luminescence (CPL). However, achieving dual-wavelength CPL in discrete cluster systems constitutes a considerable challenge. Herein, two enantiomeric pairs of heterometallic Eu-Sn oxo clusters, designated as Sn2EuL2-R/S and Sn2EuL4-R/S, were strategically synthesized using axially chiral binaphthol-phosphonate ligands. These hybrid clusters exhibit dual emission, characterized by a broad ligand-derived fluorescence band superimposed with sharp, characteristic Eu3+ f-f transitions, which enables excitation-dependent luminescence color tuning. Their emission profiles and quantum yields were found to be exquisitely adjusted by the distinct coordination environments of Sn4+ centers. Notably, Sn2EuL2-R/S demonstrates CPL activity in both the near-UV (|glum| = 1.7 × 10-3) and visible (|glum| = 3.1 × 10-2) regions. This work not only reports the first instance of dual-wavelength CPL in a lanthanide/tin oxo complex but also establishes a robust design strategy for fabricating color-tunable chiral photonic materials.