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Non-centrosymmetric Na(3)Nb(4)As(3)O(19).

ABSTRACT: A new non-centrosymmetric compound, tris-odium tetra-niobium triarsenic nona-deca-oxide, Na(3)Nb(4)As(3)O(19), has been synthesized by a solid-state reaction at 1123?K. The structure consists of AsO(4) tetra-hedra and NbO(6) octa-hedra sharing corners to form a three-dimensional framework containing two types of tunnels running along the c axis, in which the sodium ions are located. Na(+) cations occupying statistically several sites, respectively, are surrounded by seven, six and four O atoms at distances ranging from 2.08?(1) to 2.88?(4)?Å. The title structure is compared with those containing the same groups, viz.M(2)XO(13) and M(2)X(2)O(17) (M = transition metal, and X = As or P).

SUBMITTER: Cherif SF

PROVIDER: S-EPMC3343777 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature

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Non-centrosymmetric Na(3)Nb(4)As(3)O(19).

Chérif Saïda Fatma SF Hizaoui Khaled K Zid Mohamed Faouzi MF Driss Ahmed A

Acta crystallographica. Section E, Structure reports online 20120317 Pt 4

A new non-centrosymmetric compound, tris-odium tetra-niobium triarsenic nona-deca-oxide, Na(3)Nb(4)As(3)O(19), has been synthesized by a solid-state reaction at 1123 K. The structure consists of AsO(4) tetra-hedra and NbO(6) octa-hedra sharing corners to form a three-dimensional framework containing two types of tunnels running along the c axis, in which the sodium ions are located. Na(+) cations occupying statistically several sites, respectively, are surrounded by seven, six and four O atoms a ...[more]

PMID: 22589751

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