Gemmi Mauro, Klein Holger, Rageau Amelie, Strobel Pierre, Le Cras Federic
Dipartimento di Scienze della Terra Ardito Desio Università degli Studi di Milano, Via Botticelli 23, 20133 Milano, Italy.
Acta Crystallogr B. 2010 Feb;66(Pt 1):60-8. doi: 10.1107/S010876810904631X. Epub 2009 Dec 12.
A sample having stoichiometry Li[Ti(1.5)Ni(0.5)]O(4) has been synthesized to obtain a spinel structure. The resulting crystalline powder revealed a multiphase nature with spinel as the minor phase. The main phase is a new trigonal phase having a = 5.05910 (1), c = 32.5371 (1) A. The structure has been solved by direct methods working on a three-dimensional set of intensities obtained from a precession electron-diffraction experiment, and refined on synchrotron powder diffraction data in the space group P3c1. The model consists of hexagonal layers of edge-sharing octahedra occupied either by the heavy cations Ti and Ni, or preferentially by Li. On the basis of cation-site occupancies the stoichiometry becomes Li(4)Ti(8)Ni(3)O(21), which is compatible with the microanalysis results.
已合成化学计量比为Li[Ti(1.5)Ni(0.5)]O(4)的样品以获得尖晶石结构。所得结晶粉末显示出多相性质，其中尖晶石为次要相。主要相是一种新的三方相，a = 5.05910 (1)，c = 32.5371 (1) Å。该结构已通过直接法求解，该方法基于从进动电子衍射实验获得的三维强度数据集，并在空间群P3c1中根据同步辐射粉末衍射数据进行了精修。该模型由由重阳离子Ti和Ni占据或优先由Li占据的共边八面体的六边形层组成。基于阳离子位点占有率，化学计量比变为Li(4)Ti(8)Ni(3)O(21)，这与微量分析结果相符。
