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Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

X-ray diffraction and Mössbauer spectroscopy techniques were used to study the structure and hyperfine interactions of multiferroic Aurivillius compounds Bim+1Ti3Fem-3O3m+3. Samples were synthesized by two methods, that is, the solid-state sintering at various temperatures and mechanical activation in a high-energy ball mill. The compounds were obtained from a mixture of three polycrystalline powder oxides, that is, TiO2, Fe2O3 and Bi2O3. At room temperature, the Aurivillius compounds are paramagnetic materials with orthorhombic crystal structure. The c lattice parameter of the unit cell depends linearly on the m − number of layers with perovskite-like structure. Based on the Mössbauer studies, it is concluded that the hyperfine interactions parameters do not change with m number.

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Filozofia i Nauka is the property of Institute of Philosophy & Sociology of the Polish Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of the study was to determine the structure and hyperfine interactions of Bim+1Ti3Fem-3O3m+3 multiferroic Aurivillius compounds prepared by mechanical activation process. X-ray diffraction and Mössbauer spectroscopy were applied as complementary methods. After the process of mechanical milling, desired Aurivillius phases were not formed, thus, thermal treatment needed to be applied. Heating the product of mechanical activation up to 993 K allowed to obtain Aurivillius phases with relatively large amount of non-reacted hematite. However, after the material was annealed at an elevated temperature of 1073 K, the content of not fully synthesized hematite was significantly reduced. Mössbauer spectroscopy confirmed that Aurivillius compounds remain in paramagnetic state at room temperature. [ABSTRACT FROM AUTHOR]

Abstract: X-ray diffraction and Mössbauer spectroscopy were applied as complementary methods to investigate the structure and hyperfine interactions in the series of Bi m +1Ti3Fe m −3O3 m +3 Aurivillius compounds with m=4, 6, 7 and 8. Samples were synthesized by the solid-state sintering method at various temperatures. As X-ray diffraction analysis proved, the compounds formed single phases at temperature above 993K. Mössbauer studies have confirmed diffraction measurements. Compounds synthesized at 993K contained residual hematite, however these sintered at elevated temperatures were single-phased materials. Room-temperature Mössbauer spectra of Bi m +1Ti3Fe m −3O3 m +3 compounds revealed their paramagnetic properties, what is consistent with the literature data concerning the Néel temperature of these ceramics (T N is smaller than room temperature). Detailed analysis of MS spectra allowed to state that iron ions may occupy both tetrahedral and octahedral sites in the crystallographic lattice of Aurivillius compounds. [Copyright &y& Elsevier]