Influence of organic carboxylic acids on self-assembly of silver(I) complexes containing 1,2-bis(4-pyridyl)ethane ligands

Four silver(I) complexes, namely Ag₂(bpe)₂](bdc)·8H₂O (1), Ag₂(bpe)₂(da)]·4H₂O (2), Ag₄(bpe)₃(bptc)]·9H₂O (3), and Ag(bpe)₂(bpdc)₂ (4), have been successfully synthesized by the reactions between AgNO₃, 1,2-bis(4-pyridyl)ethane (bpe) and different carboxylic acids, including 1,3-benzenedicarboxylic acid (H₂bdc), diphenic acid (H₂da), 3,3′,4,4′-biphenyltetracarboxylic acid (H₄bptc), and 2,2′-bipyridine-3,3′-dicarboxylic acid (H₂bpdc). All four compounds were characterized by elemental analysis, IR spectra, and single-crystal X-ray diffraction. In (1), the Ag(I) atoms, in linear geometry, are joined into 1-D infinite cationic bpe-silver chains, and discrete bdc²⁻ anions compensate the charge of the crystal structure. In (2), the Ag(I) atoms, adopting tetrahedral and trigonal geometries, are linked by bpe and da²⁻ ligands into neutral double chains. In (3), the Ag(I) atoms, in T-shaped and linear environments, are coordinated by bpe and multidentate bptc⁴⁻ ligands to construct a 2-D network. And in (4), the Ag(I) atoms, with trigonal and T-shaped coordination geometries, are coordinated by bpe and bpdc²⁻ ligands to build up a 3-D framework. The different anions play different and important roles in directing the final crystal structures.