Combined experimental and first-principles studies of a hydrated uranyl carbonate: Insight into phonon spectra for a core environmental class of uranium materials - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Journal of Physics and Chemistry of Solids Année : 2020

Combined experimental and first-principles studies of a hydrated uranyl carbonate: Insight into phonon spectra for a core environmental class of uranium materials

Résumé

Density functional theory calculations for an environmentally important crystalline phase of a hydrated uranyl carbonate, liebigite (Ca2UO2(CO3)3·11H2O), were performed at the generalized gradient approximation Perdew-Burke-Ernzherhof functional level to support experimental interpretation of vibrational data. This phase contains the uranyl tricarbonate center (UO2(CO3)34−), which represents the coordination core of many uranium materials found in nature. This hydrated crystal is surprisingly found to have a theoretical band gap of about 2.45 eV. The electronic structure shows strong covalent U–O and C–O bonds accounting for the marked relative intensity of the Raman bands. Vibrational and photoluminescence spectra are presented. Original assignments of the vibrational lines are proposed on the basis of the theoretical analysis of the normal modes. The role of water in the vibrational properties of the crystal is discussed by investigation of, in particular, a “dry” hypothetical framework structure without water molecules.
Fichier principal
Vignette du fichier
Kalashhnyk_JPhysChemSol_2019_Combined experimental-1.pdf (1.05 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-02994262 , version 1 (08-12-2020)

Identifiants

Citer

Nataliya Kalashnyk, Dale Perry, Viktor Ivanov, Eric Faulques. Combined experimental and first-principles studies of a hydrated uranyl carbonate: Insight into phonon spectra for a core environmental class of uranium materials. Journal of Physics and Chemistry of Solids, 2020, 138, pp.109260. ⟨10.1016/j.jpcs.2019.109260⟩. ⟨hal-02994262⟩
22 Consultations
75 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More