Two new hexadecanuclear lanthanide complexes employing the 1,5-bis(salicylidene)carbohydrazide (Hbsc) ligand are reported herein. These polynuclear aggregates crystallize in the R3[combining macron] space group, which is unprecedented in a family of lanthanide complexes with such high nuclearity. Magnetic susceptibility measurements reveal weak intramolecular interactions between the magnetic centres, and in the case of compound 2 (Dy), single-molecule magnet properties are observed.

Using the Schiff‐base ligand 1,5‐bis(salicylidene)carbohydrazide (H3bsc) a unique dinuclear dysprosium(III) compound, [Dy2(µ‐OH)(bsc) (NO3)2(DMF)3(H2O)]·THF·2DMF (1·THF·2DMF), has been synthesized. The structural and magnetic properties are fully studied and single‐molecule magnetic behavior with an energy barrier (Ueff = 123 K) has been observed.