title: Vibrational spectroscopy of synthetic analogues of ankoleite, chernikovite and intermediate solid solution.
abstract: Ankoleite (K(UO2)PO4·nH2O), chernikovite (H3O(UO2)PO4·nH2O) and intermediate solid solutions are frequently encountered in the uranium ores that result from the alteration of uranium primary minerals. This paper reports a thorough FTIR and Raman study related to synthetic analogues for these minerals. First, the vibration bands associated to the UO2(2 +) uranyl ion were used to calculate the U = O bond length which appeared in good agreement with the data coming from PXRD. Then, the examination of the phosphate vibration modes in both sets of spectra confirmed the general formulation of the samples and ruled out the presence of hydrogenphosphate groups. Finally, the presence of H2O as well as protonated H3O(+) and/or H5O2(+) species was also pointed out, and could be used to clearly differentiate the various phases prepared. Vibrational spectroscopy then appeared as an efficient method for the investigation of such analogues of natural samples. It should be particularly relevant when identifying these phases in mineral ores or assemblies.
authors.affiliation: ICSM, Institut de Chimie Séparative de Marcoule, UMR 5257 CEA/CNRS/ENSCM/Université de Montpellier, Site de Marcoule - Bât. 426, BP 17171, 30207 Bagnols/Cèze cedex, France. Electronic address: nicolas.clavier@icsm.fr.
authors.forename: N
authors.initials: N
authors.lastname: Clavier
authors.affiliation: ICSM, Institut de Chimie Séparative de Marcoule, UMR 5257 CEA/CNRS/ENSCM/Université de Montpellier, Site de Marcoule - Bât. 426, BP 17171, 30207 Bagnols/Cèze cedex, France.
authors.forename: F
authors.initials: F
authors.lastname: Crétaz
authors.affiliation: ICSM, Institut de Chimie Séparative de Marcoule, UMR 5257 CEA/CNRS/ENSCM/Université de Montpellier, Site de Marcoule - Bât. 426, BP 17171, 30207 Bagnols/Cèze cedex, France.
authors.forename: S
authors.initials: S
authors.lastname: Szenknect
authors.affiliation: ICSM, Institut de Chimie Séparative de Marcoule, UMR 5257 CEA/CNRS/ENSCM/Université de Montpellier, Site de Marcoule - Bât. 426, BP 17171, 30207 Bagnols/Cèze cedex, France.
authors.forename: A
authors.initials: A
authors.lastname: Mesbah
authors.affiliation: CEA/DEN/DRCP/DIR, Site de Marcoule - Bât. 400, BP 17171, 30207 Bagnols/Cèze cedex, France.
authors.forename: C
authors.initials: C
authors.lastname: Poinssot
authors.affiliation: AREVA Mines/R&D Dpt, La Défense, 92084 Paris, France.
authors.forename: M
authors.initials: M
authors.lastname: Descostes
authors.affiliation: ICSM, Institut de Chimie Séparative de Marcoule, UMR 5257 CEA/CNRS/ENSCM/Université de Montpellier, Site de Marcoule - Bât. 426, BP 17171, 30207 Bagnols/Cèze cedex, France.
authors.forename: N
authors.initials: N
authors.lastname: Dacheux
keywords: Ankoleite; Chernikovite; Phosphate; Spectroscopy; Synthetic analogues; Uranium