Syntheses, Structures and Luminescence of Two Coordination Polymers based on 1,3,5-tris(1-imidazolyl)benzene

Two new coordination polymers (CPs), namely, {[Zn(tib)(SO4)]center dot 2H(2)O}(n) (1) and {[Cd(tib)(2,6-pydc)(H2O)]center dot H2O}(n) (2), have been hydrothermally synthesized based on the rigid 1,3,5-tris(imidazol-1-yl)benzene (tib) and 2,6-pyridinedicarboxylate (2,6-pydc(2-)) ligands. Both CPs were structurally characterized by single-crystal X-ray diffraction. In 1, the Zn(II) centers are connected by tib to generate a 2D -> 2D polythreading honeycomb 6(3) bilayer structure with the SO42- as rods. The bilayers are further connected by O-H center dot center dot center dot O hydrogen bonds to result in a 3D supramolecular structure. In 2, the Cd(II) centers are coordinated by 2,6-pydc(2-) to form binuclear Cd-2 units which are linked by mu(2)-tib into 1D chain. The 1D chains are further connected by O-H center dot center dot center dot O hydrogen bonds, leading to the 2D hydrogen bonded network. Finally, it shows a 2D -> 3D interdigitated architecture based on the 2D hydrogen bonded layers through the uncoordinated imidazole rings of tib ligands. The thermogravimetric properties and solid-state photoluminescence of 1 and 2 were investigated. [GRAPHICS] .

Automated summary

Two new coordination polymers were synthesized using rigid ligands, forming a 2D -> 3D supramolecular structure in one case and a 2D network through hydrogen bonding in another.