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DOE OSTI · 1731795

Materials Data on Na2UI6 by Materials Project

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Abstract

Na2UI6 is zeta iron carbide-derived structured and crystallizes in the orthorhombic Fmmm space group. The structure is two-dimensional and consists of two Na2UI6 sheets oriented in the (0, 0, 1) direction. Na1+ is bonded to six I1- atoms to form NaI6 octahedra that share corners with two equivalent NaI6 octahedra, edges with two equivalent NaI6 octahedra, and faces with two equivalent UI6 octahedra. The corner-sharing octahedral tilt angles are 19°. There are two shorter (3.17 Å) and four longer (3.37 Å) Na–I bond lengths. U4+ is bonded to six I1- atoms to form UI6 octahedra that share faces with four equivalent NaI6 octahedra. There are four shorter (3.03 Å) and two longer (3.05 Å) U–I bond lengths. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a 3-coordinate geometry to two equivalent Na1+ and one U4+ atom. In the second I1- site, I1- is bonded in a distorted T-shaped geometry to two equivalent Na1+ and one U4+ atom.

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36 MATERIALS SCIENCEcrystal structureI-Na-UNa2UI6

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2020-04-29. Materials Data on Na2UI6 by Materials Project. https://doi.org/10.17188/1731795

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