title: Synthesis and study of the photophysical properties of a new Eu3+ complex with 3-hydroxypicolinamide.
abstract: This work reports on the synthesis and characterization of a new complex of Eu(3+) with the 3-hydroxypicolinamide ligand (Hhpa). Here we present an approach for obtaining bis[2-carbamoyl(κO)pyridin-3-olato(κO')] lanthanide complexes, which were characterized through elemental analysis, thermal analysis, infrared and photoluminescence spectroscopies (emission, excitation, luminescence lifetimes, quantum efficiencies, Judd-Ofelt parameters and quantum yields). Although hpa can act as a bidentate ligand in different conformations, the results attest for the occurrence of a unique coordination site of low symmetry for the Eu(3+) ions, in which two anionic hpa ligands coordinate the cations through an O/O chelating system. The phosphorescence of the synthesized gadolinium complex provides the energy of the triplet state, which is determined to be at 20,830 cm(-1) over the ground state. This makes the Hhpa ligand very adequate for sensitizing the Eu(3+) luminescence, which leads to a very efficient antenna effect and opens a wide range of applications for the complex in light emitting organic-inorganic devices.
authors.affiliation: Laboratório Interdisciplinar de Eletroquímica e Cerâmica, Departamento de Química, Universidade Federal de São Carlos, Via Washington Luis, km 235, ZIP 13565-905, São Carlos, SP, Brazil. ilvrosa@ufscar.br
authors.forename: Ieda Lucia Viana
authors.initials: IL
authors.lastname: Rosa
authors.forename: Paulo Cesar de Sousa
authors.initials: PC
authors.lastname: Filho
authors.forename: Claudio Roberto
authors.initials: CR
authors.lastname: Neri
authors.forename: Osvaldo Antonio
authors.initials: OA
authors.lastname: Serra
authors.forename: Alberthmeiry Teixeira
authors.initials: AT
authors.lastname: de Figueiredo
authors.forename: José Arana
authors.initials: JA
authors.lastname: Varela
authors.forename: Elson
authors.initials: E
authors.lastname: Longo
mesh_terms: D005063:Europium / Q000737:chemistry*; D005453:Fluorescence; D008024:Ligands; D008163:Luminescent Measurements; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D055668:Photochemical Processes; D010848:Picolinic Acids / Q000737:chemistry*; D011789:Quantum Theory
chemical_list: D008024:Ligands; D009942:Organometallic Compounds; D010848:Picolinic Acids; D005063:Europium; C070035:3-hydroxypicolinamide