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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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SYNTHESIS OF ALKALI-SUBSTITUTED SR,CU OXYCARBONATES - SUPERCONDUCTIVITY IN SR2-XKXCUO2CO3 (0.25-LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-0.7)статья
Информация о цитировании статьи получена из
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Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 9 ноября 2013 г.
- Авторы: KAZAKOV SM, ANTIPOV EV, CHAILLOUT C., CAPPONI JJ, BRUNNER M., THOLENCE JL, MAREZIO M.
- Журнал: Physica C: Superconductivity and its Applications
- Том: 253
- Номер: 3-4
- Год издания: 1995
- Издательство: Elsevier BV
- Местоположение издательства: Netherlands
- Первая страница: 401
- Последняя страница: 406
- DOI: 10.1016/0921-4534(95)00539-0
- Аннотация: Sr(2-x)M(x)CuO(2)CO(3), M = Na or K, 0 less than or equal to x less than or equal to 1, samples were obtained by a high-pressure high-temperature technique using SrCO3, SrCuO2 and Na(K)CuO2 as initial reagents. The alkali-doped oxycarbonates were found to exist with Na for 0 less than or equal to x less than or equal to 1, and with K for 0 less than or equal to x less than or equal to 0.7. These oxycarbonates have a tetragonal structure derived from that of Sr2CuO2CO3. The a parameter decreases with increasing alkali ion content from a=3.9062(1) Angstrom (x=0) to a=3.8854(2) Angstrom for x(Na)=1 and to 3.8884(7) Angstrom for x(K)=0.7. Weak superstructure reflections corresponding to doubling of the cell parameters (a=2a, c=2c) were found by electron diffraction for K substituted oxycarbonate, Sr1.6K0.4CuO2CO3. The EDS analysis performed on this sample revealed that the crystallites contained an inhomogeneous K distribution and the average K concentration was found to be smaller than the nominal composition, x=0.16 and x=0.4, respectively. Superconductivity by AC susceptibility measurements was found to exist only for K substituted samples with 0.25 less than or equal to x less than or equal to 0.7, The critical temperature was found to vary in the range of 13-23 K depending on the K content. No superconductivity was observed for Na substituted samples.
- Добавил в систему: Казаков Сергей Михайлович