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Synthesis and characterization of reduced niobates CaLnNb(2)O(7), Ln=Y, Nd with a pyrochlore structureстатья
Информация о цитировании статьи получена из
Scopus,
Web of Science
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 18 июля 2013 г.
- Авторы: Istomin S.Y., Dyachenko O.G., Antipov E.V., Svensson G.
- Журнал: Materials Research Bulletin
- Том: 32
- Номер: 4
- Год издания: 1997
- Издательство: Pergamon Press Ltd.
- Местоположение издательства: United Kingdom
- Первая страница: 421
- Последняя страница: 430
- DOI: 10.1016/S0025-5408(96)00003-7
- Аннотация: The first known reduced niobates with a pyrochlore structure, CaLnNb(2)O(7) Ln = Y, Nd, have been synthesized from Ca2Nb2O7, Ln(2)O(3), and NbO2 in sealed Nb ampoules heated at 1400 degrees C for 6 h. Our studies show that these compounds have a small homogeneity region according to the formula Ca(2-x)Ln(x)Nb(2)O(7), Ln = Nd with x = 0.9, 1.0; and Ln = Y with x = 1.0, 1.1. The prepared compounds were characterized by EDX (energy dispersive X-ray) analysis, X-ray and electron diffraction, and thermogravimetric analysis. The crystal structures of CaNdNb2O7 and CaYNb2O7 were refined using X-ray and neutron powder diffraction data. CaNdNb2O7 and CaYNb2O7 have undistorted pyrochlore structures: space group Fd3m, a = 10.416(1) Angstrom and 10.3159(8) Angstrom, respectively. Resistivity measurements show that CaNdNb2O7 exhibits semiconducting behavior. Copyright (C) 1997 Elsevier Science Ltd.
- Добавил в систему: Антипов Евгений Викторович