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DOE OSTI · 1283122

Materials Data on Na2UI6 by Materials Project

Abstract

Na2UI6 is zeta iron carbide-derived structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six I1- atoms to form NaI6 octahedra that share corners with three NaI6 octahedra, corners with six UI6 octahedra, and a faceface with one NaI6 octahedra. The corner-sharing octahedra tilt angles range from 39–65°. There are a spread of Na–I bond distances ranging from 3.26–3.48 Å. In the second Na1+ site, Na1+ is bonded to six I1- atoms to form NaI6 octahedra that share corners with three NaI6 octahedra, edges with three UI6 octahedra, and a faceface with one NaI6 octahedra. The corner-sharing octahedra tilt angles range from 53–65°. There are a spread of Na–I bond distances ranging from 3.23–3.48 Å. In the third Na1+ site, Na1+ is bonded to six I1- atoms to form NaI6 octahedra that share corners with three NaI6 octahedra, corners with six UI6 octahedra, and a faceface with one NaI6 octahedra. The corner-sharing octahedra tilt angles range from 38–65°. There are a spread of Na–I bond distances ranging from 3.28–3.49 Å. In the fourth Na1+ site, Na1+ is bonded to six I1- atoms to form NaI6 octahedra that share corners with three NaI6 octahedra, edges with three UI6 octahedra, and a faceface with one NaI6 octahedra. The corner-sharing octahedra tilt angles range from 54–65°. There are a spread of Na–I bond distances ranging from 3.23–3.47 Å. In the fifth Na1+ site, Na1+ is bonded to six I1- atoms to form NaI6 octahedra that share corners with four NaI6 octahedra, corners with six UI6 octahedra, and a faceface with one NaI6 octahedra. The corner-sharing octahedra tilt angles range from 40–65°. There are a spread of Na–I bond distances ranging from 3.23–3.49 Å. In the sixth Na1+ site, Na1+ is bonded to six I1- atoms to form NaI6 octahedra that share a cornercorner with one NaI6 octahedra, edges with three NaI6 octahedra, and edges with three UI6 octahedra. The corner-sharing octahedral tilt angles are 62°. There are a spread of Na–I bond distances ranging from 3.23–3.49 Å. In the seventh Na1+ site, Na1+ is bonded to six I1- atoms to form NaI6 octahedra that share corners with two equivalent NaI6 octahedra, an edgeedge with one NaI6 octahedra, edges with three UI6 octahedra, and a faceface with one NaI6 octahedra. The corner-sharing octahedra tilt angles range from 54–57°. There are a spread of Na–I bond distances ranging from 3.20–3.49 Å. In the eighth Na1+ site, Na1+ is bonded to six I1- atoms to form NaI6 octahedra that share a cornercorner with one NaI6 octahedra, edges with two equivalent NaI6 octahedra, and edges with three UI6 octahedra. The corner-sharing octahedral tilt angles are 65°. There are a spread of Na–I bond distances ranging from 3.23–3.47 Å. There are four inequivalent U4+ sites. In the first U4+ site, U4+ is bonded to six I1- atoms to form UI6 octahedra that share corners with three equivalent NaI6 octahedra and edges with four NaI6 octahedra. The corner-sharing octahedra tilt angles range from 40–43°. There are a spread of U–I bond distances ranging from 2.92–3.07 Å. In the second U4+ site, U4+ is bonded to six I1- atoms to form UI6 octahedra that share corners with six NaI6 octahedra and edges with three NaI6 octahedra. The corner-sharing octahedra tilt angles range from 39–43°. There are a spread of U–I bond distances ranging from 2.98–3.10 Å. In the third U4+ site, U4+ is bonded to six I1- atoms to form UI6 octahedra that share corners with six NaI6 octahedra and edges with three NaI6 octahedra. The corner-sharing octahedra tilt angles range from 38–43°. There are a spread of U–I bond distances ranging from 2.99–3.08 Å. In the fourth U4+ site, U4+ is bonded to six I1- atoms to form UI6 octahedra that share corners with three equivalent NaI6 octahedra and edges with five NaI6 octahedra. The corner-sharing octahedra tilt angles range from 40–43°. There are a spread of U–I bond distances ranging from 3.00–3.11 Å. There are twenty-four 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 trigonal planar geometry to two Na1+ and one U4+ atom. In the third I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom. In the fourth I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom. In the fifth I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom. In the sixth I1- site, I1- is bonded in a distorted trigonal planar geometry to two Na1+ and one U4+ atom. In the seventh I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom. In the eighth I1- site, I1- is bonded in a distorted trigonal planar geometry to two Na1+ and one U4+ atom. In the ninth I1- site, I1- is bonded in a distorted trigonal planar geometry to two Na1+ and one U4+ atom. In the tenth I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom. In the eleventh I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom. In the twelfth I1- site, I1- is bonded in a distorted trigonal planar geometry to two Na1+ and one U4+ atom. In the thirteenth I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom. In the fourteenth I1- site, I1- is bonded in a distorted trigonal planar geometry to two Na1+ and one U4+ atom. In the fifteenth I1- site, I1- is bonded in a distorted trigonal planar geometry to two Na1+ and one U4+ atom. In the sixteenth I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom. In the seventeenth I1- site, I1- is bonded in a rectangular see-saw-like geometry to three Na1+ and one U4+ atom. In the eighteenth I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom. In the nineteenth I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom. In the twentieth I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom. In the twenty-first I1- site, I1- is bonded in a 3-coordinate geometry to two Na1+ and one U4+ atom. In the twenty-second I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom. In the twenty-third I1- site, I1- is bonded in an L-shaped geometry to one Na1+ and one U4+ atom. In the twenty-fourth I1- site, I1- is bonded in a distorted T-shaped geometry to two Na1+ and one U4+ atom.

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2020-08-03. Materials Data on Na2UI6 by Materials Project. https://doi.org/10.17188/1283122

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