학술논문
Iron-57 Mössbauer Spectroscopic Investigation of Manganese-Doped γ-Fe2 O3 .
Document Type
Article
Source
Subject
*MOSSBAUER spectroscopy
*SPECTRUM analysis
*MANGANESE spectra
*IRON analysis
*MANGANESE alloys
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Language
ISSN
0304-3843
Abstract
Manganese-doped γ-Fe2O3 has been prepared by precipitation techniques and shown by Mn K-edge XANES and EXAFS to contain Mn3+ in the octahedral sites of the spinel-related structure. The 57Fe Mössbauer spectra recorded in situ between 295 and 750 K show that conversion of the spinel-related γ-Fe2O3 -to the corundum-related α-Fe2O3-structure occurs at ca. 700 and 730 K in the samples containing ca. 1.5 and 4.1% manganese, respectively. The presence of manganese therefore stabilises the γ-Fe2O3-related structure relative to conversion to the α-Fe2O3 phase. The temperature dependence of the spectra recorded from the manganese-doped α-Fe2O3 is similar to that of pure α-Fe2O3 but with a smaller hyperfine magnetic field reflecting the presence of the manganese dopant. [ABSTRACT FROM AUTHOR]