title: Zirconium-substituted isopolytungstates: structural models for zirconia-supported tungsten catalysts.
abstract: The synthesis and characterization of a series of mixed W-Zr polynuclear Lindqvist-type complexes, deriving from hexatungstate [W6O19]2-, are described in this work. This family of compounds is built from {W5O18Zr}2- moieties as shown by the X-ray structures of the monomeric [W5O18Zr(H2O)(3-n)(DMSO)n]2- (n = 1 and 2) and dimeric [{W5O18Zr(mu-OH)}2]6- anions. A comprehensive spectroscopic study (183W NMR, FTIR, Raman, EXAFS, and EPR) of these compounds is presented. The goal of incorporating Zr(IV) cations into an oxotungstic core is to obtain spectroscopic models that could mimic the interactions that develop in supported catalysts between the active phase and the supporting oxide. This work tends to show that these molecular compounds can be regarded as soluble structural analogues of WOx/ZrO2 catalysts, which are interesting candidates for the skeletal isomerization of light n-alkanes.
authors.affiliation: Centro de Engenharia Biológica e Química, Instituto Superior Técnico, Universidade Técnica de Lisboa, Avenida Rovisco Pais, 1049-001 Lisboa, Portugal.
authors.forename: Hugo
authors.initials: H
authors.lastname: Carabineiro
authors.forename: Richard
authors.initials: R
authors.lastname: Villanneau
authors.forename: Xavier
authors.initials: X
authors.lastname: Carrier
authors.forename: Patrick
authors.initials: P
authors.lastname: Herson
authors.forename: Francisco
authors.initials: F
authors.lastname: Lemos
authors.forename: Fernando
authors.initials: F
authors.lastname: Ramôa Ribeiro
authors.forename: Anna
authors.initials: A
authors.lastname: Proust
authors.forename: Michel
authors.initials: M
authors.lastname: Che