Synthesis, structure, and magnetic study of two two-dimensional 6 ~3 honeycomb-shaped and 4~4 grid-like coordination polymetic networks based on hexa- and dodecanuclear manganese cluster units

摘要

Two 2D coordination polymetic networks compounds of [Na_3Mn ~(III)_6(μ_6-O)(thme)_4(PhCO _2)_6(H_2O)]·OH (1) and [NaMn ~(III)_4Mn~(II)_8O_2(thme) _4(N_3)(OAc)_8(AcOH)_2(CH _3O)_4] (2) with 1,1,1-tris(hydroxymethyl)-methane (H _3thme) as the ligand have been synthesized and structurally characterized by X-ray diffraction, IR spectra, and elemental analyses, where the homovalence hexanuclear Mn cluster in compound 1 and the mixed-valence dodecanuclear Mn cluster in compound 2 acted respectively as network nodes in the formation of honeycomb-shaped and rhombic grid-like layer structures. In addition, magnetic studies of 1 reveal that antiferromagnetically coupled paramagnetic cluster behavior is operative within the hexameric Mn_6 cluster and 2 exhibits antiferromagnetic coupling interactions and interesting frequency dependent in-phase as well as out-of-phase susceptibility signals are observed, respectively.