Poly[(6-carboxy­picolinato-κ(3) O (2),N,O (6))(μ(3)-pyridine-2,6-dicarboxyl­ato-κ(5) O (2),N,O (6):O (2′):O (6′))dysprosium(III)]

In the title complex, [Dy(C(7)H(3)NO(4))(C(7)H(4)NO(4))](n), one of the ligands is fully deprotonated while the second has lost only one H atom. Each Dy(III) 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 Dy(III) 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.