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DOE OSTI · 1192446

Materials Data on Zr3Tl2OF12 by Materials Project

Abstract

Tl2Zr3OF12 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Zr4+ is bonded in a 8-coordinate geometry to one O2- and seven F1- atoms. The Zr–O bond length is 2.10 Å. There are a spread of Zr–F bond distances ranging from 2.03–2.23 Å. There are three inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded to six F1- atoms to form distorted TlF6 octahedra that share corners with three equivalent TlF6 cuboctahedra and a faceface with one TlF12 cuboctahedra. There are three shorter (2.83 Å) and three longer (3.01 Å) Tl–F bond lengths. In the second Tl1+ site, Tl1+ is bonded to six equivalent F1- atoms to form distorted corner-sharing TlF6 cuboctahedra. The corner-sharing octahedral tilt angles are 71°. All Tl–F bond lengths are 2.84 Å. In the third Tl1+ site, Tl1+ is bonded to twelve F1- atoms to form face-sharing TlF12 cuboctahedra. There are six shorter (2.77 Å) and six longer (3.19 Å) Tl–F bond lengths. O2- is bonded in a distorted trigonal planar geometry to three equivalent Zr4+ atoms. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a bent 150 degrees geometry to two equivalent Zr4+ atoms. In the second F1- site, F1- is bonded in a 2-coordinate geometry to two equivalent Zr4+ and two Tl1+ atoms. In the third F1- site, F1- is bonded in a 3-coordinate geometry to two equivalent Zr4+ and one Tl1+ atom. In the fourth F1- site, F1- is bonded in a distorted single-bond geometry to one Zr4+ and two Tl1+ atoms.

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2020-07-20. Materials Data on Zr3Tl2OF12 by Materials Project. https://doi.org/10.17188/1192446

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