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By adopting trilacunary [A-α-GeW9O34]4–as precursor under hydrothermal conditions, two novel polyoxometalates (POMs) substituted by crescent-shaped Ln5clusters, namely, Na4K4(H2pip)6(H2O)10{Ln10(μ3-OH)2(H2O)10[α(1,8)-GeW10O38]2[β(4,11)-GeW10O38]2}·29H2O (1-Lafor Ln = La, 1-Cefor Ln = Ce, pip = piperazine) were successfully synthesized. The one-dimensional chains of two lanthanide substituted POMs are constructed from edge-sharing of nanoclusters with size of 2.5 × 2.9 × 1.0 nm3, which contain two crescent-shaped five-nuclearity Ln5clusters and two [β(4,11)-GeW10O38]12–polyanions. Furthermore, 1-Laexhibits good ion-conducting performance with proton conduction activation energy of 0.49 eV, which follows vehicular mechanism. 1-Ceillustrates anti-ferromagnetic behavior, which can be attributed to spin–orbital coupling interactions within the crescent-shaped Ln5clusters.

The assemblies of a p-conjugated organic luminophore ligand (p-tr2Ph) and d10transition metal cations produce two metal–organic frameworks (MOFs), [Zn(μ4-p-tr2Ph)(μ2-NO3)]·NO3(1), and {[Cd2(μ4-1,4-BDC)2(μ4-p-tr2Ph)(μ2-DMF)(H2O)2]}·2H2O (2) (p-tr2Ph = 1,4-phenylene-4,4′-bis(1,2,4-triazole), DMF = N,N′-dimethylformamide, 1,4-H2BDC = 1,4-dicarboxybenzene). Compound 1is a new three-dimensional (3D) cationic framework with left-handed helical channels constructed from a right-handed helical chain [Zn(μ2-tr)2(μ2-NO3)]n. Compound 2possesses a 3D 3-fold interpenetrated neutral framework with one-dimensional distorted hexagonal channels in each MIL-88 type single-net. The compounds 1and 2both exhibit blue fluorescence. Notably, the intensity-based luminescent thermometer measurements reveal that compound 2is extremely more linear with temperature, has finer reversibility within three cycles, and a wider temperature range than those of compound 1, indicating that compound 2is a more desirable low-temperature detector.