Acta Crystallographica Section E (Jul 2010)
Bis(μ-2,4-dihydroxybenzoato-κ2O:O′)bis[aqua(2,4-dihydroxybenzoato-κO)(1,10-phenanthroline-κ2N,N′)cadmium(II)]
Abstract
In the title centrosymmetric dimeric CdII complex, [Cd2(C7H5O4)4(C12H8N2)2(H2O)2], the CdII cation is coordinated by a bidentate phenanthroline (phen) ligand, three dihydroxybenzoate (dhba) anions and one water molecule in a distorted CdN2O4 octahedral geometry. Among the dhba anions, two anions bridge two CdII cations to form the dimeric complex with significant different Cd—O bond distances of 2.2215 (19) and 2.406 (2) Å. The centroid–centroid distance of 3.4615 (19) Å between two nearly parallel benzene rings of the dhba and phen ligands coordinating to the same CdII cation indicates the existence of intramolecular π–π stacking in the complex. Extensive O—H...O hydrogen bonding and intermolecular weak C—H...O hydrogen bonding help to stabilize the crystal structure. One hydroxy group of the monodentate dhba ligand is disordered over two sites with a site-occupancy ratio of 0.9:0.1.