Synthesis, structure, magnetocaloric effect and DFT calculations of a MnII cluster-based inorganic coordination polymer

Abstract

A new Mn inorganic coordination polymer, formulated as {(H3O)2[Mn3(SO4)3(μ3-OH)2(H2O)2]}n (1), was synthesized by a hydrothermal reaction and characterized magnetically. Structural analysis reveals that 1 features a MnII3-hydroxyl-sulfate layer which is extended into a 3D supramolecular framework through hydrogen bonds with interlayer hydronium ions. Magnetic measurements indicate that 1 exhibits homospin ferrimagnetic behavior with a (5/2, 10/2) spin topology and a 1/3 magnetization plateau. The spontaneous magnetization induced by ferrimagnetic behavior was observed. Single-crystal magnetic measurements indicate that the a-axis of 1 is the magnetic easy axis. Notably, 1 exhibits significant MCE with the maxiumu −ΔSm value of 14.58 J Kg−1 K−1 for ΔH = 8 T at 16 K. Moreover, the density functional theory (DFT) calculations were performed to explain the ferrimagnetic behavior.