Synthesis, crystal structure and properties of a 3D coordination polymer [Zn(HCO2)2(4,4′-bipy)]∞

Reactions of ZnO, HCO2H, and 4,4'-bipy (molar ratio=1:3:1.25) in H2O/DMF (volume ratio=13:1) at 60 degrees C afforded [Zn(HCO2)(2)(4,4'-bipy)](infinity) with 75% yield. It crystallizes in the tetragonal symmetry with space group P4(3)2(1)2 and lattice parameters: a=b=0.79675(5) nm, c=1.7627(2) nm, V=1. 1190(3) nm(3), Z=4, D-c=1.850 g/cm(3), M-r=311.60, F(000)=632, mu=22.07 cm(-1), R-1=0.0183, and wR(2)=0.0483. The X-ray analysis reveals that the zinc ion is octahedrally coordinated by two N atoms from one 4,4'-bipy ligand and four O atoms from four HCO2- anions. The ZnN2O4 octahedra are connected via two bridging 4.4'-bipy ligands and four bridging HCO2- anions, forming an interesting 3D scaffold structure. The thermal and photoluminescent properties of the title compound were also studied.