A New 3D Coordination Polymer Based on Pentanuclear Cd(II) Rod-Shaped Secondary Building Unit: Synthesis,Crystal Structure and Luminescent Property

A new coordination polymer [Cd_2.5(μ₃-OH)(L)₂(bipy)]_n (1). (L = 1,2-naphthalene dicarboxylate, bipy = 4,4′-bipyridine), was obtained under hydrothermal condition. The structure of 1 has been determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis and IR spectrum. Single-crystal X-ray diffraction analyses reveal that complex 1 crystallizes in triclinic system, Pī space group. Complex 1 possesses a 3D pcu net based on a pentanuclear Cd(II) cluster. Each pentanuclear Cd(II) cluster links with neighboring ones and generates a rod-shaped secondary building unit, which is further extended by bipy ligands to forms a three-dimensional network. Furthermore, the luminescent properties of this complex and the free ligand have been investigated. Complex 1 can be excited directly and emit strong soild-state fluorescence at room temperature, which may make them excellent candidates for fluorescent materials.