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Rietveld refinement of the langbeinite-type mixed-metal phosphate K2Ni0.5Zr1.5(PO4)3.

ABSTRACT: Dipotassium [nickel(II) zirconium(IV)] tris-(orthophosphate) was prepared from a self-flux in the system K2O-P2O5-NiO-K2ZrF6. The title compound belongs to the langbeinite family and is built up from two [MO6] octa-hedra [M = Ni:Zr with mixed occupancy in ratios of 0.21?(4):0.79?(4) and 0.29?(4):0.71?(4), respectively] and [PO4] tetra-hedra inter-linked via vertices into a (3) ?[M 2(PO4)3] framework. Two independent K(+) cations are located in large cavities of the framework, with coordination numbers to O(2-) anions of nine and twelve. The K, Ni, and Zr sites are located on threefold rotation axes.

SUBMITTER: Zatovsky IV

PROVIDER: S-EPMC4120588 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Rietveld refinement of the langbeinite-type mixed-metal phosphate K2Ni0.5Zr1.5(PO4)3.

Zatovsky Igor V IV

Acta crystallographica. Section E, Structure reports online 20140618 Pt 7

Dipotassium [nickel(II) zirconium(IV)] tris-(orthophosphate) was prepared from a self-flux in the system K2O-P2O5-NiO-K2ZrF6. The title compound belongs to the langbeinite family and is built up from two [MO6] octa-hedra [M = Ni:Zr with mixed occupancy in ratios of 0.21 (4):0.79 (4) and 0.29 (4):0.71 (4), respectively] and [PO4] tetra-hedra inter-linked via vertices into a (3) ∞[M 2(PO4)3] framework. Two independent K(+) cations are located in large cavities of the framework, with coordination n ...[more]

PMID: 25161511

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