The electronic properties of mixed valence hydrated europium chloride thin film

Abstract : We investigate the electronic properties of a model mixed-valence hydrated chloride europium salt by means of high resolution photoemission spectroscopy (HRPES) and resonant photoemission spectroscopy (RESPES) at the Eu 3d → 4f and 4d → 4f transitions. From the HRPES spectra, we have determined that the two europium oxidation states are homogeneously distributed in the bulk and that the hydrated salt film is exempt from surface mixed valence transition. From the RESPES spectra, the well separated resonant contributions characteristic of divalent and trivalent europium species (4f$^6$ and 4f$^7$) final states, respectively) are accurately extracted and quantitatively determined from the resonant features measured at the two edges. The partial absorption yield spectra, obtained by integrating the photoemission intensity in the valence-band region, can be well reproduced by atomic multiplet calculation at the M$_{4,5}$ (3d-4f) absorption edge and by an asymmetric Fano-like shape profile at the N$_{4,5}$) (4d-4f) absorption edge. The ratio of Eu$^{2+}$ and Eu$^{3+}$ species measured at the two absorption edges matches with the composition of the mixed valence europium salt as determined chemically. We have demonstrated that the observed spectroscopic features of the mixed valence salt are attributed to the mixed-valence ground state rather than surface valence transition. HRPES and RESPES spectra provide reference spectra for the study of europium salts and their derivatives.
Type de document :
Article dans une revue
Physical Chemistry Chemical Physics, Royal Society of Chemistry, 2015, 17, pp.18403. 〈10.1039/c5cp01256b〉
Liste complète des métadonnées

Littérature citée [40 références]  Voir  Masquer  Télécharger

https://hal-cea.archives-ouvertes.fr/cea-01349746
Contributeur : Dominique Girard <>
Soumis le : lundi 2 octobre 2017 - 14:03:15
Dernière modification le : jeudi 6 septembre 2018 - 15:18:04

Fichier

c5cp01256b.pdf
Fichiers éditeurs autorisés sur une archive ouverte

Identifiants

Citation

M.G. Silly, Fabrice Charra, Francois Lux, G. Lemercier, F. Sirotti. The electronic properties of mixed valence hydrated europium chloride thin film . Physical Chemistry Chemical Physics, Royal Society of Chemistry, 2015, 17, pp.18403. 〈10.1039/c5cp01256b〉. 〈cea-01349746〉

Partager

Métriques

Consultations de la notice

165

Téléchargements de fichiers

44