Poly[[tetraaquatetrakis[μ3-5-(pyridine-4-carboxamido)isophthalato]cobalt(II)digadolinium(III)] tetrahydrate]

Abstract

In the centrosymmetric polymeric title compound, {[CoGd2(C14H8N2O5)4(H2O)4]·4H2O}n, the GdIII cation is coordinated by one water molecule and four pyridine-4-carboxamidoisophthalate (L) anions in a distorted square-antiprismatic arrangement, while the CoII cation, located on an inversion center, is coordinated by two pyridyl-N atoms, two carboxylate-O atoms and two water molecules in a distorted octahedral geometry. The asymmetric unit contains two anionic L ligands: one bridges two Gd cations and one Co cation through two carboxyl groups and one pyridine-N atom; the other bridges two Gd cations and one Co cation through two carboxyl groups and the uncoordinated pyridine-N atom is hydrogen-bonded to the adjacent coordinated water molecule. Extensive O—H...O and N—H...O hydrogen bonds are present in the crystal structure.