Cl–-Templated Assembly of Novel Peanut-like Ln40Ni44 Heterometallic Clusters Exhibiting a Large Magnetocaloric Effect

Two novel and fascinating high-nuclearity lanthanide-transition (4f–3d) heterometallic clusters were obtained based on an anion-template (Cl – ) and ligand-controlled approach, formulated as [Gd 40 Ni 44 (CO 3 ) 12 (CH 3 COO) 4 (IDA) 44 (C 2 O 4 )(μ 2 -O) 4 (μ 3 -OH) 60 (μ 3 -O) 6 (H 2 O) 12 ]·Cl 10 ·20H 2 O (abbreviated as Gd 40 Ni 44, 1 ) and [Eu 40 Ni 44 (CO 3 ) 12 (CH 3 COO) 6 (IDA) 44 (C 2 O 4 )(μ 2 -O) 4 (μ 3 -OH) 62 (μ 3 -O) 4 (H 2 O) 12 ]·Cl 10 ·23H 2 O (abbreviated as Eu 40 Ni 44, 2 ), where H 2 IDA = iminodiacetic acid and H 2 C 2 O 4 = oxalic acid. Structural analysis exhibits that the compounds 1 and 2 were both constructed by two enticing bowl-like anion units Ln 20 Ni 22, featuring peanut-like structures. Besides, the assembly of Ln 20 Ni 22 was templated by five Cl – ions. Magnetically, compound 1 shows a significant magnetocaloric effect, with −Δ S m = 36.05 J kg –1 K –1 at 3 K for Δ H = 7 T.