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LiCo2As3O10: une nouvelle structure a tunnels inter-connectes.

ABSTRACT: 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.

SUBMITTER: Ben Smida Y

PROVIDER: S-EPMC3684868 | biostudies-other | 2013 Jun

REPOSITORIES: biostudies-other

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LiCo2As3O10: une nouvelle structure à tunnels inter-connectés.

Ben Smida Youssef Y Guesmi Abderrahmen A Driss Ahmed A

Acta crystallographica. Section E, Structure reports online 20130531 Pt 6

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 thr ...[more]

PMID: 23794970

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LiCo2As3O10: une nouvelle structure a tunnels inter-connectes.

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LiCo2As3O10: une nouvelle structure à tunnels inter-connectés.

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