Syntheses, structures and photoluminescent properties of two zinc(II) coordination polymers based on aromatic polycarboxylate and 1,4-bis(imidazol-1-ylmethyl)benzene

Hydrothermal reaction of Zn(NO3)2·6H2O with benzene-1,2,3-tricarboxylic acid (H3BTC) or 5-bromoisophthalic acid (H2BIPA) in the presence of 1,4-bis(imidazol-1-ylmethyl)benzene (bix) produced two novel coordination polymers [Zn2(OH)(BTC) (bix)]·H2O (1) and Zn(BIPA)(bix) (2), which were characterized by single-crystal X-ray diffraction, elemental analysis, IR and thermoanalysis. Complex 1 is a novel example of the 2D (3,4)-connected nets with (42·6)(42·63·8) topology. In 2, the BIPA and bix ligands linked the Zn(II) atoms into a deeply corrugated 2D sheet. The corrugated 2D sheets polycatenate each other in a parallel manner yielding a rare 2D → 3D parallel polycatenation net. Thermal and luminescent properties of two complexes have also been investigated.