Инд. авторы:	Vereshchagin O.S., Rozhdestvenskaya I.V., Frank-Kamenetskaya O.V., Zolotarev A.A., Mashkovtsev R.I.
Заглавие:	Crystal chemistry of Cu-bearing tourmalines
Библ. ссылка:	Vereshchagin O.S., Rozhdestvenskaya I.V., Frank-Kamenetskaya O.V., Zolotarev A.A., Mashkovtsev R.I. Crystal chemistry of Cu-bearing tourmalines // American Mineralogist. - 2013. - Vol.98. - Iss. 8-9. - P.1610-1616. - ISSN 0003-004X. - EISSN 1945-3027.
Внешние системы:	DOI: 10.2138/am.2013.4408; SCOPUS: 2-s2.0-84882793408; WoS: 000323584000028;
Реферат:	eng: The crystal structures of two elbaites from the Paraiba deposit with copper contents of 3.51 and 1.61 wt% CuO [a = 15.881(1), 15.840(3); c = 7.112(1), 7.1028(9), respectively], as well as a synthetic Cu-bearing olenite with a CuO content of 8.39 wt% [a = 15.840(4), c = 7.091(1)] have been refined to R-indices of 2.2, 3.1, and 4.1% using X ray single-crystal diffraction. On the basis of original and published data (for six structures) the crystal-chemical relationships of copper-bearing tourmalines has been analyzed. It is shown that copper cations and cations of other 3d elements (Mn, Zn, Fe) occupy almost exclusively the Y site. Such an ordered distribution results in a change of the size of the Y-octahedra. There is an inverse correlation between the content of 3d elements (mainly Cu2+ cations) and Al3+ cations in the Y-octahedron and also between the value of and the content of Al3+ cations in the Y site. The direct correlation between values of -distance in the structures of Cu-bearing elbaites and the parameters (a, c) of the unit cell have been found. Distortions of polyhedra in the structures of Cu-bearing elbaites are similar, and significantly higher than those present in the structure of the synthetic Cu-bearing olenite.
Ключевые слова:	Brazil; tourmaline; olenite; crystal structure; crystal chemistry; copper; Paraiba; X ray structure refinement; Tourmaline; Paraiba; Cu-rich elbaite; Cu-bearing olenite; Crystal chemistry; cation;
Издано:	2013
Физ. характеристика:	с.1610-1616