A hydrostable and bromine-functionalized manganese-organic framework with luminescence sensing of Hg2+ and antiferromagnetic properties

A hydrostable and bromine-functionalized MOF with a sxd topology constructed from tetranuclear clusters, {[Mn-2(Bript)(2)(4,4'-bpy)(.5)(DMF)]center dot(H2O)}(n) (1) (H(2)Bript = 4-Bromoisophthalic acid, 4,4'-bpy = 4,4'-bipyridine, DMF = dimethylformamide) was synthesized and structurally characterized. TGA and PXRD results show high thermal and water stability for the framework. 1 displays a 3D framework with the channel of 4.6 x 4.6 angstrom(2) along the c axis. The framework exhibits a reversible and highly selective luminescent sensing function with respect to Hg2+ cation. Magnetic measurements reveal that the presence of weak antiferromagnetic couplings between the four Mn(II) ions in 1.