Syntheses, crystal structures and photoluminescence of three coordination polymers with 2,3-pyrazinedicarboxylic acid and N-donor ligands

The reactions between Cd(OAC)(2)/Cu(NO3)(2) and mixed ligands (2,3-pyrazinedicarboxylic acid (pzdc) and N-donor ligands) under different reaction conditions give the three title complexes 1, 2 and 3. There is a (4,8) net 2D network structure and a rectangular grid network structure in the cadmium complexes [Cd(pzdc)(phen)] center dot H2O (1) and Cd-2(pzdC)(2)(4,4'-bpy)(H2O)(2) (2), respectively. The complex [CU4(pzdC)(4)(phen)2(H'0)(4)] - I OH,O (3) has a I D zigzag chain structure. The influences of coordination modes of the pzdc ligand and N-donor ligands on the superstructural diversity have been discussed. Complexes 1 and 2 exhibit strong fluorescent emission bands in the solid state at room temperature. The EPR spectrum of 3 is typical for a square-pyramidal geometry of copper (II) ions. (c) 2007 Elsevier Ltd. All rights reserved.