title: Differences and Similarities between Lanthanum and Rare-Earth Iodate Anhydrous Polymorphs: Structures, Thermal Behaviors, and Luminescent Properties.
abstract: The Ln(IO3)3(HIO3)y(y = 1 or 1.33) compounds are isostructural with the La(IO3)3(HIO3)yphases, but thermal studies reveal different behaviors. On the one hand, the partial thermal decompositions of these lanthanide compounds lead to the Ln(IO3)3formulation, with a room temperature structure different from the β-La(IO3)3obtained from La(IO3)3(HIO3)y. On the other hand, the partial thermal decompositions of the La1-xLnx(IO3)3(HIO3)ycompounds prepared with lanthanides ions (Ce, Pr, Nd, Sm, Eu, Gd, and Yb) lead to acentric β-La1-xLnx(IO3)3. As for β-La(IO3)3, reversible structural transitions from β-La1-xLnx(IO3)3to centrosymmetric γ-La1-xLnx(IO3)3are observed. Differential scanning calorimetry analyses of La1-xLnx(IO3)3solid solutions show that the transition temperatures vary with the lanthanide concentration in the solid solution. A transition is observed only up to a certain fraction of lanthanide-ion substitution; this substitution limit decreases with the cationic radius of the lanthanide ion. Finally, the β-La1-xNdx(IO3)3and β-La1-xYbx(IO3)3phases are investigated by luminescence spectroscopy.
authors.affiliation: Université Grenoble Alpes, Institut NEEL , F-38042 Grenoble, France.|CNRS, Institut NEEL , F-38042 Grenoble, France.|INSA, UMR 6226, Institut des Sciences Chimiques de Rennes , 20 Avenue des buttes de Coësmes, F-35708 Rennes, France.
authors.forename: Yan
authors.initials: Y
authors.lastname: Suffren
authors.affiliation: Université Grenoble Alpes, Institut NEEL , F-38042 Grenoble, France.|CNRS, Institut NEEL , F-38042 Grenoble, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Leynaud
authors.affiliation: Université Grenoble Alpes, Institut NEEL , F-38042 Grenoble, France.|CNRS, Institut NEEL , F-38042 Grenoble, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Plaindoux
authors.affiliation: Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière , F-69622, Lyon, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Brenier
authors.affiliation: Université Grenoble Alpes, Institut NEEL , F-38042 Grenoble, France.|CNRS, Institut NEEL , F-38042 Grenoble, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Gautier-Luneau