Poly[(6-carboxypicolinato-κ3O2,N,O6)(μ3-pyridine-2,6-dicarboxylato-κ5O2,N,O6:O2′:O6′)dysprosium(III)]

Abstract

In the title complex, [Dy(C7H3NO4)(C7H4NO4)]n, one of the ligands is fully deprotonated while the second has lost only one H atom. Each DyIII ion is coordinated by six O atoms and two N atoms from two pyridine-2,6-dicarboxylate and two 6-carboxypicolinate ligands, displaying a bicapped trigonal-prismatic geometry. The average Dy—O bond distance is 2.40 Å, some 0.1Å longer than the corresponding Ho—O distance in the isotypic holmium complex. Adjacent DyIII ions are linked by the pyridine-2,6-dicarboxylate ligands, forming a layer in (100). These layers are further connected by π–π stacking interactions between neighboring pyridyl rings [centroid–centroid distance = 3.827 (3) Å] and C—H...O hydrogen-bonding interactions, assembling a three-dimensional supramolecular network. Within each layer, there are other π–π stacking interactions between neighboring pyridyl rings [centroid–centroid distance = 3.501 (2) Å] and O—H...O and C—H...O hydrogen-bonding interactions, which further stabilize the structure.