title: Li15Al3Si6 (Li14.6Al3.4Si6), a compound displaying a heterographite-like anionic framework.
abstract: The title compound, lithium aluminium silicide (15/3/6), crystallizes in the hexagonal centrosymmetric space group P6(3)/m. The three-dimensional structure of this ternary compound may be depicted as two interpenetrating lattices, namely a graphite-like Li(3)Al(3)Si(6) layer and a distorted diamond-like lithium lattice. As is commonly found for LiAl alloys, the Li and Al atoms are found to share some crystallographic sites. The diamond-like lattice is built up of Li cations, and the graphite-like anionic layer is composed of Si, Al and Li atoms in which Si and Al are covalently bonded [Si-Al = 2.4672 (4) A].
authors.affiliation: Laboratoire des Agrégats Moléculaires et Matériaux Inorganiques, UMR 5072 CC15, Université de Montpellier II, Sciences et Techniques du Languedoc, 2 Place Eugène Bataillon, 34095 Montpellier Cedex 5, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Spina
authors.forename: Monique
authors.initials: M
authors.lastname: Tillard
authors.forename: Claude
authors.initials: C
authors.lastname: Belin