Аннотация:Using ferrocenecarboxylic acid (FcCO2H) and triethanolamine (H3tea) as ligands, the isostructural heterotrimetalliccomplexes [LnIII2CrIII2(OH)2(FcCO2)4(NO3)2(Htea)2]·2MePh·2THF (Ln = Tb (1), Dy (2), Ho (3), Er (4), and Y (5); Fc = (η5-C5H4)(η5-C5H5)Fe; H3tea = N(CH2CH2OH)3) were obtained. In all of the complexes which possess a defective dicubane structure, twodoubly deprotonated triethanolamine ligands chelate the chromium ions. However, during the synthesis of 1, an isomericcomplex 1a in which Tb3+ is chelated by triethanolamine as a tetradentate ligand, was also isolated as a few single crystals.Magnetic susceptibility measurements revealed dominant antiferromagnetic interactions in the {LnIII2CrIII2} cores of 1-4leading to complexes with an uncompensated magnetic moment, while weak Cr-Cr ferromagnetic interactions weredetected in the Y analogue. Complexes 1, 2, and 3 display single-molecule magnet properties dominated by an Orbach-typerelaxation mechanism with magnetization reversal barriers (∆/kB) estimated around 54, 75, and 47 K, respectively. The Dycomplex exhibits a magnetization hysteresis in an applied magnetic field at temperatures below 4 K. Thermolysis of thecomplexes was studied by TGA and DSC techniques; the final products obtained under air atmosphere contain mixed oxideCr0.75Fe1.25O3 and heterotrimetallic oxide LnCr1-xFexO3 (with x ≈ 0.75) phases.