57Fe Mössbauer spectroscopy of annealed metamict davidite

• Autorzy: Malczewski D. , Frąckowiak J. , Galuskin E.
• Konferencja: Proceedings of the All-Polish Seminar on Mössbauer Spectroscopy OSSM'06, June 18-21, 2006, Koszęcin, Poland
• Języki publikacji: EN

Abstrakty

EN

This paper reports preliminary results of 57Fe Mössbauer spectroscopy and X-ray diffraction (XRD) studies of metamict davidite samples (La,Ce,Ca,Th)(Y,U,Fe)(Ti,Fe,Mn)20(O,OH)38 after high temperature annealing in an argon atmosphere. The Mössbauer spectra show a gradual decrease of quadrupole splitting and line width values of an Fe3+ doublet with increasing annealing temperature. Rather unexpected feature of these spectra for an Fe2+ doublet is a considerable increase of the line width with progressive crystallinity and a simultaneous decrease of both quadrupole splitting and isomer shift values. Changes of the hyperfine parameters as a function of the annealing temperature appeared as sensitive indicators of the thermal recrystallization process of metamict davidite similar to metamict silicates.

Słowa kluczowe

EN

davidite; metamict minerals; recrystallization; Mössbauer spectroscopy

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2007
• Tom: Vol. 52, supl. 1
• Strony: 81--84
• Opis fizyczny: Bibliogr. 8 poz., rys.

Twórcy

autor

Malczewski D.

autor

Frąckowiak J.

autor

Galuskin E.

• Faculty of Earth Sciences, University of Silesia, 60 Będzińska Str., 41-200 Sosnowiec, Poland, Tel.: [phone], Fax: [phone],

Bibliografia

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• 8. Weber WJ, Ewing RC, Catlow CRA et al. (1998) Radiation effects in crystalline ceramics for the immobilization of high-level nuclear waste and plutonium. J Mater Res 13:1434−1484