JRP CALL information
Supported By

European Commission

Short description of the work
The Talisman JRP C05-14 was dedicated to the investigation of structural properties of uranium and americium mixed dioxides by XAS (X-ray absorption spectroscopy) and EELS (electron energy loss spectroscopy). XAS measurements were performed at the ROBL beamline of the European Synchrotron Radiation Facility (ESRF). One UO2 and five (U,Am)O2 samples with an Am/(U+Am) ratio equal to 15%, 30%, 50%, 60% and 70% were studied. XANES (X-ray absorption near edge structure) and EXAFS (Extended X-ray Absorption Fine Structure) spectra were recorded at both U and Am edges (U LIII, U LII and Am LIII) at four different temperatures: 15 K, 100 K, 150 K and 300 K. The analysis of the data will now be performed at CEA. XANES spectra will allow identifying the oxidation states of uranium and americium in the different compounds, whereas the EXAFS data will provide information on the local cation structure, which will be coupled with the EELS data. Moreover, thanks to the acquisition of EXAFS spectra at 4 different temperatures, it will be possible to determine the ratio between structural and thermal disorder in the Debye-Waller factors.

Main visitor contact data
Name: Enrica Epifano
Organisation: CEA

JRP Identification
JRP nr: TALI-C05-14
JRP title: Determination of O/(U+Am) ratios, charge distribution and local structure in uranium-americium mixed oxides using XAS and EELS measurements
JRP scope: Scope 3: Actinide materials

Visited Associated Pooled Facility
Visited APF during the stay: HZDR - ROBL
Name of the APF Contact Person: Andreas Scheinost, Christoph Hennig

Other APF and organisation involved in the JRP
Other organisations involved:
Other APF involved in the project: JRC-ITU - Labs & Hot-cells

Description of the work done at the associated pooled facility
Start date of the stay: 12/10/2015
End date of the stay: 12/15/2015
Quantity of access: 5
Access Unit: Days
Misc.: Work during week-ends

Other APF visitors of the JRP during the stay
Visitor 2: Philippe Martin
Visitor 3: Jacques Lechelle