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Titolo:
The true crystal structure of Li17M4 (M=Ge, Sn, Pb)-revised from Li22M5
Autore:
Goward, GR; Taylor, NJ; Souza, DCS; Nazar, LF;
Indirizzi:
Univ Waterloo, Dept Chem, Waterloo, ON N2L 3G1, Canada Univ Waterloo Waterloo ON Canada N2L 3G1 em, Waterloo, ON N2L 3G1, Canada
Titolo Testata:
JOURNAL OF ALLOYS AND COMPOUNDS
fascicolo: 1-2, volume: 329, anno: 2001,
pagine: 82 - 91
SICI:
0925-8388(20011114)329:1-2<82:TTCSOL>2.0.ZU;2-9
Fonte:
ISI
Lingua:
ENG
Soggetto:
LITHIUM; OXIDE;
Keywords:
energy storage materials; crystal growth; crystal structure and symmetry; high temperature alloys; diffraction;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
18
Recensione:
Indirizzi per estratti:
Indirizzo: Nazar, LF Univ Waterloo, Dept Chem, 200 Univ Ave W, Waterloo, ON N2L 3G1, Canada Univ Waterloo 200 Univ Ave W Waterloo ON Canada N2L 3G1 , Canada
Citazione:
G.R. Goward et al., "The true crystal structure of Li17M4 (M=Ge, Sn, Pb)-revised from Li22M5", J ALLOY COM, 329(1-2), 2001, pp. 82-91

Abstract

Single crystal studies of the compounds Li17Ge4, Li17Sn4 and Li17Pb4, previously thought to be of stoichiometry Li22M5 (M=Ge, Sn, Ph) are presented. Their space group is F (4) over bar 3m, rather than the F23 previously reported for Sri and Pb, with a = 18.756(2) Angstrom, 19.690(2) Angstrom and 19.842(1) Angstrom for the Ge, Sn and Ph compounds, respectively, with very good refinements, particularly for the tin structure (R(F greater than or equal to 4 sigma (F)) = 1.85% for Ge, 1.91% for Sn and 2.3% for Pb). Comparison with the related structure of Li21Si5 reveals that as one progresses down Group IV, there is a variation in the occupation of the lithium tetrahedra about the tetrahedral Wickoff sites based on the space apportioned by thesurrounding metal atoms. Partial or complete occupation of some tetrahedral sites increases from Si to Ph resulting in centred tetrahedral Li-5 groups replacing Li-4 units, and hence stoichiometries that can be effectively described as Li21Si5 ('Li16.8Si4'); Li(21 + 3/16)Ge5 ('Li17Ge4'); Li(21 + 5/16)Sn5 ('Li17Sn4'); and Li(21 + 1/4)Pb5 (or Li17Pb4). (C) 2001 Elsevier Science B.V. All rights reserved.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 04/07/20 alle ore 04:18:39