Structural Stability of Quaternary ACuFeS(2) (A = Li, K) Phases: A Computational Approach

Conejeros, S; Alemany, P; Llunell, M; Sánchez V.; Llanos J.; Padilla-Campos, L

Abstract

At ambient conditions, the quaternary sulfides LiCuFeS 2 and KCuFeS 2 present totally different crystal structures: while LiCuFeS 2 crystallizes in a trigonal CaAl 2Si 2-type structure, a tetragonal ThCr 2Si 2-like structure is found for KCuFeS 2. In this work, we present a computational study describing first the changes in the structural preference of the ACuFe 2 phases as a function of the alkali ion and second, the structural stability of the CuFeS 2 phases obtained by electrochemical removal of the alkali cations from the two ACuFeS 2 compounds. A high copper mobility is found to be responsible for the observed metastability of the layered trigonal CuFeS 2 phase obtained by delithiation of LiCuFeS 2. In contrast, the tetragonal CuFeS 2 structure obtained removing potassium from KCuFeS 2 is predicted to be stable, both from the kinetic and thermodynamic points of view. The possibility of stabilizing mixed Li xCu 1-xFeS 2 phases with a ThCr 2Si 2-type structure and the mobility of lithium in these is also explored. © 2011 American Chemical Society.

Más información

Título según WOS: Structural Stability of Quaternary ACuFeS(2) (A = Li, K) Phases: A Computational Approach
Título según SCOPUS: Structural stability of quaternary ACuFeS 2 (A = Li, K) phases: A computational approach
Título de la Revista: INORGANIC CHEMISTRY
Volumen: 51
Número: 1
Editorial: AMER CHEMICAL SOC
Fecha de publicación: 2012
Página de inicio: 362
Página final: 369
Idioma: English
URL: http://www.scopus.com/inward/record.url?eid=2-s2.0-84855396815&partnerID=40&md5=780c958de5f22321228e0b8d057d6460
DOI:

10.1021/ic201758j

Notas: ISI, SCOPUS