LiCo2As3O10: une nouvelle structure à tunnels inter-connectés.

Acta Crystallogr Sect E Struct Rep Online

Laboratoire de Matériaux et Cristallochimie, Faculté des Sciences, El Manar II, 2092 Tunis, Tunisia.

Published: June 2013

The title compound, lithium dicobalt(II) triarsenate, LiCo2As3O10, was synthesized by a solid-state reaction. The As atoms and four out of seven O atoms lie on special positions, all with site symmetry m. The Li atoms are disordered over two independent special (site symmetry -1) and general positions with occupancies of 0.54 (7) and 0.23 (4), respectively. The structure model is supported by bond-valence-sum (BVS) and charge-distribution (CHARDI) methods. The structure can be described as a three-dimensional framework constructed from bi-octahedral Co2O10 dimers edge-connected to As3O10 groups. It delimits two sets of tunnels, running parallel to the a and b axes, the latter being the larger. The Li(+) ions are located within the inter-sections of the tunnels. The possible motion of the alkali cations has been investigated by means of the BVS model. This simulation shows that the Li(+) motion appears to be easier mainly along the b-axis direction and that this material may possess inter-esting conduction properties.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3684868PMC
http://dx.doi.org/10.1107/S1600536813013548DOI Listing

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