A ‘kagome dual’ (kgd) sheet based on triangular rigid ligand: Synthesis, structure, photoluminescence and anion exchange properties

A cadmium coordination polymer with ‘Kagomé dual’ (kgd) sheet structure, {[Cd(tipa)2]·2NO3·5DMF}n (1), has been synthesized by employing an elongated triangular rigid N-containing ligand tris(4-(1H-imidazol-yl)phenyl)amine (tipa) and structurally characterized by X-ray single-crystal diffraction. The Cd(II) ion is six coordinated with N atoms from tipa ligands, forming a CdN6 octahedron geometry. The tridentate tipa ligand connects the Cd(II) ions into a 2D sheet. Topologically, if the triangular tipa ligand and the Cd(II) ions are regarded as 3- and 6-connected nodes respectively, the overall 2D sheet can be simplified to a (3,6)-connected kgd net with a Schläfli symbol of (43)2(46·66·83). Moreover, the photoluminescence at 298 and 77 K and anion exchange properties of 1 were also discussed.