title: Amino-Functionalized Layered Crystalline Zirconium Phosphonates: Synthesis, Crystal Structure, and Spectroscopic Characterization.
abstract: Two new layered zirconium phosphonates functionalized with amino groups were synthesized starting from aminomethylphosphonic acid in the presence of different mineralizers, and their structures were solved from powder X-ray diffraction data. Their topologies are unprecedented in zirconium phosphonate chemistry: the first, of formula ZrH[F3(O3PCH2NH2)], prepared in the presence of hydrofluoric acid, features uncommon ZrO2F4 units and a remarkable thermal stability; the second, of formula Zr2H2[(C2O4)3(O3PCH2NH2)2]·2H2O, prepared in the presence of oxalic acid, is based on ZrO7 units with oxalate anions coordinated to the metal atom, which were never observed before in any zirconium phosphonate. In addition, the structure of another compound based on (2-aminoethyl)phosphonic acid is reported, which was the object of a previously published study. This compound has layered α-type structure with -NH3(+) groups located in the interlayer space. All of the reported compounds were further characterized by means of vibrational spectroscopy, which provided important information on fine structural details that cannot be deduced from the powder X-ray diffraction data.
authors.affiliation: Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institute , 5232 Villigen-PSI, Villigen, Switzerland.
authors.forename: Marco
authors.initials: M
authors.lastname: Taddei
authors.affiliation: Department of Chemistry Biology and Biotechnology, University of Perugia , Via Elce di Sotto 8, 06123 Perugia, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Sassi
authors.affiliation: Department of Chemistry Biology and Biotechnology, University of Perugia , Via Elce di Sotto 8, 06123 Perugia, Italy.
authors.forename: Ferdinando
authors.initials: F
authors.lastname: Costantino
authors.affiliation: Department of Pharmaceutical Sciences, University of Perugia , Via del Liceo 1, 06123 Perugia, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Vivani