Heterobimetallic hexanuclear [MnΙΙΙ4LnΙΙΙ2] clusters: A rare MnΙΙΙ4NdΙΙΙ2 example exhibiting slow relaxation of magnetization

Abstract

Reactions of lanthanide perchlorates and manganese acetate with Schiff-base ligand (H₄L = 2-(((2-hydroxy-3-methoxyphenyl)methylene)amino)-2-(hydroxymethyl)-1,3-propanediol) in methanol in the presence of triethylamine yielded two hexanuclear heterometallic clusters of general formula [Mn₄^ΙΙΙLn₂^ΙΙΙ(H₂L)₂(HL)₂(CH₃COO)₄(CH₃O)₂(CH₃OH)₄](ClO₄)₂·6CH₃OH [Ln = La^ΙΙΙ (1), Nd^ΙΙΙ (2)]. 1 and 2 are isostructural, with the metal centres consisting of a nonplanar [Mn₄^ΙΙΙLn₂^ΙΙΙ(μ₂-O)₈(μ₃-OR)₂]⁸⁺ core. Variable-temperature solid state magnetic susceptibilities measurements of 1 and 2 in the temperature 2–300 K were performed, indicating dominant antiferromagnetic exchange interactions between the metal centres in both compounds. Alternating current (ac) susceptibility data for 2 displays out-of-phase signal suggesting slow relaxation of magnetization whereas no out-of-phase signal is observed in 1, highlighting the incorporation of lighter lanthanide leads to SMM property.