57Fe Mössbauer spectroscopy and X-ray diffraction study of gadolinites REE2Fe2+Be2Si2O10 from Lower Silesia (Poland) and Ytterby (Sweden)

• Autorzy: Malczewski D.
• Konferencja: Proceedings of the All-Polish Seminar on Moessbauer Spectroscopy OSSM'2002, June 9-12, 2002, Goniądz, Poland
• Języki publikacji: EN

Abstrakty

EN

This paper reports the results of 57Fe Mössbauer spectroscopy, X-ray diffraction (XRD) and gamma-ray spectroscopy studies of partially metamict gadolinites from Szklarska Poręba and Zimnik (Lower Silesia, Poland), a fully metamict gadolinite sample from Ytterby (Sweden) and a crystalline sample obtained after annealing of a fragment of the sample from Ytterby at 1373 K in an argon atmosphere. Both fully metamict and crystalline gadolinite show divalent iron exclusively in octahedral coordination. Changes of the amplitudes ratio of high energy to low energy absorption peaks from Fe2+ quadrupole doublets are strictly correlated with calculated absorbed alpha-dose and the metamictization stages of the gadolinite specimens. In this respect, one of the samples is in conflict with the estimated radiation dose based on age and radionuclide concentrations. In this case, Mössbauer spectroscopy shows that the sample had to be naturally annealed over geologic time.

Słowa kluczowe

EN

gadolinite; Mössbauer spectroscopy; X-ray diffraction

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2003
• Tom: Vol. 48,suppl.1
• Strony: 41--44
• Opis fizyczny: Bibliogr. 14 poz., rys.

Twórcy

autor

Malczewski D.

• Faculty of Earth Sciences, University of Silesia, 60 Będzińska Str., 41-200 Sosnowiec, Poland, Tel.: [phone] ext. 316, Fax: [phone]

Bibliografia

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