title: Photophysical studies of europium coordination polymers based on a tetracarboxylate ligand.
abstract: Reaction of europium sulfate octahydrate with p-terphenyl-3,3″,5,5″-tetracarboxylic acid (H4ptptc) in a mixed solvent system has afforded three new coordination polymers formulated as {[Eu(ptptc)0.75(H2O)2]·0.5DMF·1.5H2O}n (1), {[Me2H2N]2 [Eu2(ptptc)2(H2O)(DMF)]·1.5DMF·7H2O}n (2), and {[Eu(Hptptc)(H2O)4]·0.5DMF·H2O}n (3). Complex 1 exhibits a three-dimensional (3D) metal-organic framework based on {Eu2(μ2-COO)2(COO)4}n chains, complex 2 shows a 3D metal-organic framework constructed by [Eu2(μ2-COO)2(COO)6](2-) dimetallic subunits, and complex 3 features a 2D layer architecture assembling to 3D framework through π···π interactions. All complexes exhibit the characteristic red luminescence of Eu(III) ion. The triplet state of ligand H4ptptc matches well with the emission level of Eu(III) ion, which allows the preparation of new optical materials with enhanced luminescence properties. The luminescence properties of these complexes are further studied in terms of their emission quantum yields, emission lifetimes, and the radiative/nonradiative rates.
authors.affiliation: State Key Laboratory of Structure Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, 350002, People's Republic of China.
authors.forename: Yan-Li
authors.initials: YL
authors.lastname: Gai
authors.forename: Fei-Long
authors.initials: FL
authors.lastname: Jiang
authors.forename: Lian
authors.initials: L
authors.lastname: Chen
authors.forename: Yang
authors.initials: Y
authors.lastname: Bu
authors.forename: Kong-Zhao
authors.initials: KZ
authors.lastname: Su
authors.forename: Shaeel A
authors.initials: SA
authors.lastname: Al-Thabaiti
authors.forename: Mao-Chun
authors.initials: MC
authors.lastname: Hong
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry*; D056831:Coordination Complexes / Q000737:chemistry*; D005063:Europium / Q000737:chemistry*; D049449:Luminescence; D008958:Models, Molecular; D011108:Polymers / Q000737:chemistry*
chemical_list: D002264:Carboxylic Acids; D056831:Coordination Complexes; D011108:Polymers; D005063:Europium