title: Structure solution of the new titanate Li4Ti8Ni3O21 using precession electron diffraction.
abstract: 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.
authors.affiliation: Dipartimento di Scienze della Terra Ardito Desio Università degli Studi di Milano, Via Botticelli 23, 20133 Milano, Italy. mauro.gemmi@unimi.it
authors.forename: Mauro
authors.initials: M
authors.lastname: Gemmi
authors.forename: Holger
authors.initials: H
authors.lastname: Klein
authors.forename: Amelie
authors.initials: A
authors.lastname: Rageau
authors.forename: Pierre
authors.initials: P
authors.lastname: Strobel
authors.forename: Federic
authors.initials: F
authors.lastname: Le Cras