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Reinvestigation of KMg(1/3)Nb(2/3)OPO(4).

ABSTRACT: The crystal structure of potassium magnesium niobium oxide phosphate, KMg(1/3)Nb(2/3)OPO(4), which was described in the space group P4(3)22 [McCarron & Calabrese, (1993 ?). J. Solid State Chem.102, 354-361], has been redetermined in the revised space group P4(1). Accordingly, the assignment of the space group P4(3)22 and, therefore, localization of K at a single half-occupied position, as noted in the previous study, proved to be an artifact. As a consequence, two major and two minor positions of K are observed due to the splitting along [001], as first noted for KTiOPO(4) structure analogues. It has been shown that the geometry of the {M(II) (1/3)Nb(2/3)O(6/2)}(?) framework is almost unaffected by the lowering of symmetry.

SUBMITTER: Babaryk AA

PROVIDER: S-EPMC2983719 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature

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Reinvestigation of KMg(1/3)Nb(2/3)OPO(4).

Babaryk Artem A AA Bon Vladimir V Zatovsky Igor V IV Slobodyanik Nikolay S NS Pekhnyo Vasily V

Acta crystallographica. Section E, Structure reports online 20100210 Pt 3

The crystal structure of potassium magnesium niobium oxide phosphate, KMg(1/3)Nb(2/3)OPO(4), which was described in the space group P4(3)22 [McCarron & Calabrese, (1993 ▶). J. Solid State Chem.102, 354-361], has been redetermined in the revised space group P4(1). Accordingly, the assignment of the space group P4(3)22 and, therefore, localization of K at a single half-occupied position, as noted in the previous study, proved to be an artifact. As a consequence, two major and two minor positions o ...[more]

PMID: 21580195

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