Single‐Molecule Magnet and Magnetothermal Properties of Two‐Dimensional Polymers Containing Heterometallic [Cu ₅5 Ln ₂2 ] (Ln = Gd ^{IIIIII and Dy IIIIII ) Motifs}

摘要

> The reaction of a compartmental ligand N , N′ ‐bis(3‐methoxysalicylidene)‐1,3‐diamino‐2‐propanol (LH ₃ ) with Cu II and Ln III salts under solvothermal conditions afforded two‐dimensional coordination polymers, [{Cu ₅ Gd ₂ (L) ₂ (μ ₃ ‐OH) ₄ (NO ₃ ) ₄ (μ‐OH ₂ ) ₂ }(NO ₃ ) ₂ ] _∞ ( 1 ) and [{Cu ₅ Dy ₂ (L) ₂ (μ ₃ ‐OH) ₄ (NO ₃ ) ₄ (MeOH) ₂ }(NO ₃ ) ₂ ] _∞ ( 2 ). A detailed study of the magnetic properties of the two coordination polymers reveals that the [Cu ₅ Dy ₂ ] analogue shows single‐molecule magnet (SMM) behavior with an energy barrier of about 12 K with τ ₀ = 10 –6 s under zero‐dc field, while the [Cu ₅ Gd ₂ ] analogue shows magnetocaloric effect with a –Δ S _m value of 17.55 J?kg –1 ?K –1 at T = 2 K (Δ B = 5 T). Interesting