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The ?-polymorph of uranium phosphide selenide.

ABSTRACT: ?-UPSe was synthesized from the reaction of U(2)Se(3), P and Se in a CsCl flux in a fused-silica tube. It crystallizes with four formula units in the tetra-gonal space group I4/mmm in the UGeTe structure type. The asymmetric unit comprises one U (site symmetry 4mm), one Se (4mm), and one P (mmm.) atom. The U atom is coordinated in a monocapped square-anti-prismatic arrangement, where the square face is formed by P atoms and the other five vertices are Se atoms. The P site is disordered about a mirror plane, showing half-ocupancy for each of the two resulting P atoms. The title structure is related to that of ?-UPSe, which crystallizes with two formula units in the tetra-gonal space group P4/nmm in the PbFCl structure type.

SUBMITTER: Oh GN

PROVIDER: S-EPMC3238582 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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The β-polymorph of uranium phosphide selenide.

Oh George N GN Ibers James A JA

Acta crystallographica. Section E, Structure reports online 20111130 Pt 12

β-UPSe was synthesized from the reaction of U(2)Se(3), P and Se in a CsCl flux in a fused-silica tube. It crystallizes with four formula units in the tetra-gonal space group I4/mmm in the UGeTe structure type. The asymmetric unit comprises one U (site symmetry 4mm), one Se (4mm), and one P (mmm.) atom. The U atom is coordinated in a monocapped square-anti-prismatic arrangement, where the square face is formed by P atoms and the other five vertices are Se atoms. The P site is disordered about a m ...[more]

PMID: 22199473

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