|
ИСТИНА |
Войти в систему Регистрация |
ФНКЦ РР |
||
Synthesis and characterization of new strontium iron (II) phosphates, SrFe2 (PO4)(2) and Sr9Fe1.5 (PO4)(7)статья
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 18 июля 2013 г.
- Авторы: Belik A.A., Lazoryak B.I., Pokholok K.V., Terekhina T.P., Leonidov I.A., Mitberg E.B., Karelina V.V., Kellerman D.G.
- Журнал: Journal of Solid State Chemistry
- Том: 162
- Номер: 1
- Год издания: 2001
- Издательство: Elsevier B.V.
- Местоположение издательства: Netherlands
- Первая страница: 113
- Последняя страница: 121
- DOI: 10.1006/jssc.2001.9363
- Аннотация: New strontium iron(II) orthophosphates, SrFe2(PO4)(2) and Sr9Fe1.5(PO4)(7), were synthesized by the solid state method at 1170 K. They were characterized by X-ray powder diffraction, thermal analysis in air, magnetic susceptibility, and the IR and Mossbauer spectroscopy methods. Mossbauer spectroscopy confirmed the presence of only Fe2+ cations in both compounds. SrFe2(PO4)(2), crystallizes in a monoclinic system with a = 10.5376(7) Angstrom, b = 6.8529(4) Angstrom, c = 9.3658(6) Angstrom, beta = 109.498(5)degrees. The crystal structure of Sr9Fe1.5(PO4)(7) was refined by the Rietveld method: space group R-3m; Z = 3; a = 10.6102(1) Angstrom, c = 19.7135(1) Angstrom with R-wp = 3.00% (S = 1.51), R-p = 2.35%, R-B = 3.44%, R-F = 1.72%. A second-harmonic-generation study showed that the structures of these two compounds have a center of symmetry. The crystal structure of Sr9Fe1.5(PO4)(7) is related to that of beta -Ca-3(PO4)(2) and alpha -Sr-3(PO4)(2), but is topologically more similar to that of beta -Ca-3(PO4)(2). Tetrahedra P1O(4) and strontium cations in the M3 sites are disordered in the structure of Sr9Fe1.5(PO4)(7). The octahedral M5 site is fully occupied and the M4 site is quarter-occupied by iron cations. SrFe2(PO4)(2) and Sr9Fe1.5(PO4)(7) are stable in air up to 750 and 810 K, respectively. (C) 2001 Academic Press.
- Добавил в систему: Лазоряк Богдан Иосипович