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Two new metal–organic frameworks [Mn 3 (MMA) 2 (INA) 2 ] n ( 1 ) and [Cu 2 (FA)(INA) 3 (H 2 O)] n ( 2 , FA = formate) were prepared solvothermally by using mixed methylmalonic acid (H 2 MMA) and isonicotinic acid (HINA) as the initial reactants. Single-crystal X-ray diffraction analyses reveal that complex 1 has a 3D framework structure consisting of 2D [Mn 3 ] layer units and INA connector, and 2 owns a 2D pillar-layered structure constituted of mononuclear-Cu(II)-based 2D layer unit and paddle-wheel dinuclear Cu(II) cluster-based pillared linker, which further interspersed with each other to form a 3-fold interpenetrated framework with a (4 8 .6 2 )- SP topology. The magnetic studies show that 1 displays antiferromagnetic ordering at low temperature, and a strong antiferromagnetic interaction exists in 2 . [ABSTRACT FROM AUTHOR]

The reaction of the decadentate ligand tpmen (H4tpmen = N,N,N'N'-tetrakis[(6-carboxypyridin-2-yl)methyl]ethylenediamine) with MnCl2·4H2O in aqueous solution gives a homodinuclear complex [Mn2(H2O)2(tpmen)]·16H2O, which has been characterized by elemental analysis, thermal gravimetric and single-crystal X-ray diffraction analysis. The complex crystallizes in the orthorhombic system, space group Cmca, a = 28.786(5) Å, b = 11.5033(19) Å, c = 14.437(2) Å, Z = 8, R1 = 0.0432, wR2 = 0.0786. The tpmen ligand contains four picolinate groups, two of which bind each Mn(II) to form a dinuclear complex. The geometry around the Mn(II) is distorted octahedral with two nitrogen and two oxygen atoms from the picolinate groups and two oxygen atoms from coordinated water. The variable-temperature (2-300 K) magnetic susceptibilities shows an antiferromagnetic interaction between Mn(II) ions. [ABSTRACT FROM AUTHOR]