A single-molecule magnet featuring a parallelogram [Dy4(OCH2–)4] core and two magnetic relaxation processes

Abstract

An alkoxido-bridged tetranuclear Dy(III) complex, [Dy₄(H₃L)₂(OAc)₆]·2EtOH {1, H₆L = 1,3-bis[tris(hydroxymethyl)methylamino]propane}, has been solvothermally synthesized and characterized. An X-ray crystallographic study revealed that complex 1 possesses a novel “parallelogram” [Dy₄(OCH₂–)₄] core, and a new binding mode η³:η³:η¹:η¹:η¹:η²:μ⁴ of the Bis-tris propane ligand was observed. Magnetic investigations indicated that it is a single-molecule magnet (SMM), showing two distinct magnetic relaxation processes with the energy barriers of 44 K and 107 K, respectively. Such a two-step magnetic relaxation process could be well described by the sum of two modified Debye functions.