Luminescent cluster-organic frameworks constructed from predesigned supertetrahedral {Ln4Zn6} secondary building units.

3d–4f heterometallic supertetrahedral clusters with the formula of Ln4Zn6(μ6-O)L4(CH3COO)6(NO3)4(CH3OH)4(H2O)2 (1-Ln, Ln = Eu, Gd, Tb, H3L = 2-(hydroxymethyl)-2-(pyridin-4-yl)-1,3-propanediol) have been successfully introduced as stable secondary building units (SBUs) to construct new cluster-organic frameworks with tunable emission, demonstrating a promising strategy for developing new optical materials.