Characterisation of amorphous state of REE2Fe2+Be2Si2O10 by spectroscopic methods.

• Autorzy: Malczewski D. , Skrzypek D. , Molak A.
• Konferencja: International Conference on Fabrication and Properties of Metallic Nanomaterials, Warsaw, 17-19 June, 2004.
• Języki publikacji: EN

Abstrakty

EN

This paper presents 57Fe Moessbauer spectroscopy, electron paramagnetic resonance (EPR), transmission electron microscopy (TEM), X-ray diffraction (XRD), gamma-ray spectroscopy and dielectric permitivity spectroscopy studies of fully metamict gadolinite REE2Fe2+Be2Si2O10 from Ytterby (Sweden). X-ray and electron diffraction patterns of the sample show complete lack of long range order (LRO). 57Fe Moessbauer spectroscopy of the sample revealed only Fe3+ ions definitely located in octahedral coordinations, similar to thye crystalline structure of gadolinite. The EPR resonance spectrum is complete and its features corespond to Gd3+ and Mn2+ centers. The Gd3+ centers show low-symmetry of local crystal field and may be characterized by distribution of spin-Hamiltonian parameters such as: g-factor and fine-structure parameters. The temperature dependence of utensity proves that a fraction of gadolinium ions interact by superexchange type mechanism and reveals that these exchange interactions are of the antiferromagnetic type Mn2+ centers and the character of Mn2+ EPR spectra indicate that this spectra are atributed to isolated manganium ions. The AC conductivity exhibits thermally activated behavior above 420 K whereas the dielectric constant shows a step-like anomaly near 230 K.

Słowa kluczowe

EN

amorphous state; spectriscopic method; spectroscopy

PL

stan amorficzny; metoda spektroskopowa; spektroskopia

• Wydawca: Komitet Nauki o Materiałach PAN
• Czasopismo: Archives of Materials Science
• Rocznik: 2004
• Tom: Vol. 25, nr 4
• Strony: 561--571

Twórcy

autor

Malczewski D.

• Faculty of Earth Science, University of Silesia, ul. Będzińska 60, 41-200 Sosnowiec, Poland

autor

Skrzypek D.

• Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland

autor

Molak A.

• Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland

• Faculty of Earth Science, University of Silesia, ul. Będzińska 60, 41-200 Sosnowiec, Poland

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