Synthesis and Characterization of 3d-3d Homo- and Heterometallic Coordination Polymers with Mixed Ligands

Two new 3d-3d homo- and heterometallic coordination polymers with mixed organic ligands, namely, [Zn2(IBC)(BTC)(H2O)]·H2O (1) and [CdCo(IBC)(BTC)(H2O)] (2) [HIBC = 3,5-di(1H-imidazol-1-yl)benzoic acid, H3BTC = 1,3,5-benzenetricarboxylic acid], have been synthesized and fully characterized by X-ray diffraction, IR, elemental analysis, thermogravimetric analysis, photoluminescence, and magnetic measurements. Complex 1 with homonuclear Zn(II) is a rare three-dimensional (3D) (3,6)-connected rtl (rutile) framework with [Zn2O2] and [Zn2(OCO)2] two different kinds of binuclear Zn(II) secondary building units (SBUs). While complex 2 with heteronuclear Cd(II) and Co(II) atoms is a 3D framework based on [Cd2O2] and [Co2O2] SBUs. In 2, the SBUs are extended into an infinite eight-connected rare hex-type (hexagonal-type) network. The binuclear [Co2O2] SBU in 2 shows antiferromagnetic interactions. Both 1 and 2 were constructed by the same ligands, however with completely different structures and topologies, the results revealed that the coordination geometries of the metal centers have a subtle influence on the structure of the complexes.