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DOE OSTI · 1652170

Materials Data on Na2UI6 by Materials Project

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Abstract

Na2UI6 is beta Vanadium nitride-derived structured and crystallizes in the trigonal R3 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six I1- atoms to form NaI6 octahedra that share corners with three equivalent NaI6 octahedra, corners with six equivalent UI6 octahedra, and a faceface with one NaI6 octahedra. The corner-sharing octahedra tilt angles range from 43–58°. There are three shorter (3.25 Å) and three longer (3.28 Å) Na–I bond lengths. In the second Na1+ site, Na1+ is bonded to six I1- atoms to form NaI6 octahedra that share corners with three equivalent NaI6 octahedra, edges with three equivalent UI6 octahedra, and a faceface with one NaI6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are three shorter (3.18 Å) and three longer (3.36 Å) Na–I bond lengths. U4+ is bonded to six I1- atoms to form UI6 octahedra that share corners with six equivalent NaI6 octahedra and edges with three equivalent NaI6 octahedra. The corner-sharing octahedral tilt angles are 43°. There are three shorter (3.01 Å) and three longer (3.03 Å) U–I bond lengths. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a distorted trigonal planar geometry to two Na1+ and one U4+ atom. In the second I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom.

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36 MATERIALS SCIENCEcrystal structureI-Na-UNa2UI6

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2020-07-20. Materials Data on Na2UI6 by Materials Project. https://doi.org/10.17188/1652170

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