title: CuLi2Sn and Cu2LiSn: Characterization by single crystal XRD and structural discussion towards new anode materials for Li-ion batteries.
abstract: The stannides CuLi2Sn (CSD-427095) and Cu2LiSn (CSD-427096) were synthesized by induction melting of the pure elements and annealing at 400 °C. The phases were reinvestigated by X-ray powder and single-crystal X-ray diffractometry. Within both crystal structures the ordered CuSn and Cu2Sn lattices form channels which host Cu and Li atoms at partly mixed occupied positions exhibiting extensive vacancies. For CuLi2Sn, the space group F-43m. was verified (structure type CuHg2Ti;a=6.295(2) Å;wR2(F²)=0.0355 for 78 unique reflections). The 4(c) and 4(d) positions are occupied by Cu atoms and Cu+Li atoms, respectively. For Cu2LiSn, the space groupP63/mmcwas confirmed (structure type InPt2Gd;a=4.3022(15) Å,c=7.618(3) Å;wR2(F²)=0.060 for 199 unique reflections). The Cu and Li atoms exhibit extensive disorder; they are distributed over the partly occupied positions 2(a), 2(b) and 4(e). Both phases seem to be interesting in terms of application of Cu-Sn alloys as anode materials for Li-ion batteries.
authors.affiliation: Institute of Inorganic Chemistry (Materials Chemistry), University of Vienna, Währingerstraße 42, A-1090 Wien, Vienna.
authors.forename: Siegfried
authors.initials: S
authors.lastname: Fürtauer
authors.affiliation: Institute of Mineralogy and Crystallography, University of Vienna, Althanstraße 14, A-1090 Wien, Vienna.
authors.forename: Herta S
authors.initials: HS
authors.lastname: Effenberger
authors.affiliation: Institute of Inorganic Chemistry (Materials Chemistry), University of Vienna, Währingerstraße 42, A-1090 Wien, Vienna.
authors.forename: Hans
authors.initials: H
authors.lastname: Flandorfer
keywords: Crystal structure; Cu–Li–Sn; Li-ion battery; Lithium; Single-crystal XRD; Stannide