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Crystal Structure of the NaCa(Fe2+, Al, Mn)(5)[Si8O19(OH)](OH)(7)center dot 5H(2)O Mineral: A New Representative of the Palygorskite Groupстатья
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: Rastsvetaeva R.K., Aksenov S.M., Verin I.A.
- Журнал: Crystallography Reports
- Том: 57
- Номер: 1
- Год издания: 2012
- Издательство: Maik Nauka/Interperiodica Publishing
- Местоположение издательства: Russian Federation
- Первая страница: 43
- Последняя страница: 48
- DOI: 10.1134/S1063774511040225
- Аннотация: A specimen of a new representative of the palygorskite-sepiolite family from Aris phonolite (Namibia) is studied by single-crystal X-ray diffraction. The parameters of the triclinic (pseudomono-clinic) unit cell are as follows: a = 5.2527(2) angstrom, b = 17.901(1) angstrom, c = 13.727(1) angstrom, alpha = 90.018(3)degrees, beta = 97.278(4)degrees, and gamma = 89.952(3)degrees. The structure is solved by the direct methods in space group P (1) over bar and refined to R = 5.5% for 4168 vertical bar F vertical bar > 7 sigma(F) with consideration for twinning by the plane perpendicular to y (the ratio of the twin components is 0.52 : 0.48). The crystal chemical formula (Z = 1) is (Na1.6K0.2Ca0.2)[Ca-2(Fe3.62+Al1.6Mn0.8)(OH)(9)(H2O)(2)][(Fe3.92+Ti0.1)( OH)(5)(H2O)(2)][Si16O38(OH)(2)]center dot 6H(2)O, where the compositions of two ribbons of octahedra and a layer of Si tetrahedra are enclosed in brackets. A number of specific chemical, symmetrical, and structural features distinguish this mineral from other minerals of this family, in particular, from tuperssuatsiaite and kalifersite, which are iron-containing representatives with close unit cell parameters.
- Добавил в систему: Аксенов Сергей Михайлович