Synthesis and crystal structure of metal-organic frameworks [Ln2(pydc-3,5)3(H2O)9]n3nH2O (Ln = Sm, Eu, Gd, Dy; pydc-3,5 = pyridine-3,5-dicarboxylate) along with the photoluminescent property of its europium one

Rare-earth metal-organic frameworks, [Ln2(pydc)3(H2O)9]n3nH2O (Ln = Sm, Eu, Gd, Dy; pydc = pyridine-3,5-dicarboxylate), were synthesized and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The solid-state photoluminescence measurements exhibited red light-emitting characteristic of europium (III) coordination polymer. The title compounds consist of one-dimensional dual chains, in which each metal atom is nine-coordinated with oxygen atoms.