Structural Diversity of Four Metal–Organic Frameworks Based on Linear Homo/Heterotrinuclear Nodes with Furan-2,5-dicarboxylic Acid: Crystal Structures and Luminescent and Magnetic Properties

Four new homo- and heterometallic metal–organic
frameworks
(MOFs) based on linear homo/heterotrinuclear nodes, namely, {[NH2(CH3)2]2­[Co3(FDA)4­(CH3OH)2]}n (1), {[NH2(CH3)2]2­[Co3(FDA)4]­·2DMF}n (2), {[Gd2Co­(FDA)4(H2O)4]·2H2O}n (3), and {[Dy2Co­(FDA)4(glycol)2]·2H2O}n (4) (H2FDA = furan-2,5-dicarboxylic
acid), were obtained under solvothermal conditions and characterized
by single crystal X-ray diffraction, magnetic susceptibility, and
luminescence measurements. The building blocks of four MOFs are linear
trinuclear clusters stabilized by carboxylic groups, but the three-dimensional
frameworks are different. MOFs 1 and 2 are
both pcu nets with a point symbol of (412.63), whereas MOFs 3 and 4 exhibit 3,10T9 and tfz-d nets with the point symbols
of (418.624.83)­(43)2 and (43)2(46.618.84), respectively. Magnetic susceptibility measurements
indicate that there are antiferromagnetic interactions in 1–3, while 4 displays interesting
ferromagnetic interactions between Co­(II) and Dy­(III) ions. Luminescence
investigation of 4 shows intense and characteristic emission
bands of Dy­(III) ions in the solid state.