|
ИСТИНА |
Войти в систему Регистрация |
ИСТИНА ИНХС РАН |
||
Cationic Clathrate I Si46-xPxTey (6.6(1) <= y <= 7.5(1), x <= 2y): Crystal Structure, Homogeneity Range, and Physical Propertiesстатья
Статья опубликована в высокорейтинговом журнале
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: Zaikina I.V., Kovnir K.A., Burkhardt U., Schnelle W., Haarmann F., Schwarz U., Grin Yu, Shevelkov A.V.
- Журнал: Inorganic Chemistry
- Том: 48
- Номер: 8
- Год издания: 2009
- Издательство: American Chemical Society
- Местоположение издательства: United States
- Первая страница: 3720
- Последняя страница: 3730
- DOI: 10.1021/ic8023887
- Аннотация: A new cationic clathrate I Si46-xPxTey (6.6(1) <= y <= 7.5(1), x <= 2y at 1375 K) was synthesized from the elements and characterized by X-ray powder diffraction, thermal analysis, scanning electron microscopy, wavelength dispersive X-ray spectroscopy (WDXS), neutron powder diffraction, and P-31 NMR spectroscopy. The thermal behaviors of the magnetic susceptibility and resistivity were investigated as well. Si46-xPxTey reveals a wide homogeneity range due to the presence of vacancies in the tellurium guest positions inside the smaller cage of the clathrate I structure. The vacancy ordering in the structure of Si46-xPxTey causes the change of space group from Pm3n (ideal clathrate I) to Pm3 accompanied by the redistribution of P and Si atoms over different framework positions. Neutron powder diffraction confirmed that P atoms preferably form a cage around the vacancy-containing tellurium guest position. Additionally, P-31 NMR spin-spin relaxation experiments revealed the presence of sites with different coordination of phosphorus atoms. Precise determination of the composition Of Si46-xPxTey by WDXS showed slight but noticeable deviation (x <= 2y) of phosphorus content from the Zintl counting scheme (x = 2y). The compound is diamagnetic while resistivity measurements show activated behavior or that of heavily doped semiconductors. Thermal analysis revealed high stability of the investigated clathrate: Si46-xPxTey melts incongruently at similar to 1460 K in vacuum and is stable in air against oxidation up to 1295 K.
- Добавил в систему: Шевельков Андрей Владимирович