Influence of Different Organic Carboxylate Anions on the Crystal Structure of Silver(I) Coordination Polymers

The reaction of AgNO3, 4,4'-bipyridine (bpy) and 2,2'-bipyridine-3,3'-dicarboxylic acid (H(2)bpdc)/2,2'-biquinoline-4,4'-dicarboxylic acid (H(2)bqdc)/1,3-benzenedicarboxylic acid (H(2)bdc) gave rise to block-like crystals of [Ag-4(bpy)(2)(bpdc)(2)]center dot 13H(2)O (1), [Ag-2(bpy)(bqdc)(H2O)]center dot 4.5H(2)O (2) and [Ag-2(bpy)(2)(H2O)(2)](bdc)center dot 3H(2)O (3) by slow evaporation. All the three complexes contain sandwich-like crystal structures, in which anionic sheets built up from different anions (bpdc(2-), bqdc(2-) and bdc(2-)) and lattice water molecules via rich hydrogen-bonding interactions are inserted between the cationic silver complex layers, and the abundant Ag center dot center dot center dot Ag, Ag center dot center dot center dot N and pi-pi stacking interactions further strengthen the 3D frameworks. The lattice water molecules are situated among the framework of crystal structure and stabilized by rich hydrogen-bonding interactions, and lattice water molecules may play a role in the orientation of organic anions in the crystal packing. Additionally, the thermal properties of 1, 2 and 3 were also discussed in detail.