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DOE OSTI · 1705407

Materials Data on Hf3AgHg3F20 by Materials Project

Abstract

Hf3AgHg3F20 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. Hf4+ is bonded to seven F1- atoms to form HfF7 pentagonal bipyramids that share corners with two equivalent HfF7 pentagonal bipyramids, corners with four equivalent HgF7 pentagonal bipyramids, an edgeedge with one AgF8 hexagonal bipyramid, and an edgeedge with one HgF7 pentagonal bipyramid. There are a spread of Hf–F bond distances ranging from 1.99–2.13 Å. Ag2+ is bonded to eight F1- atoms to form distorted AgF8 hexagonal bipyramids that share corners with two equivalent AgF8 hexagonal bipyramids, edges with three equivalent HfF7 pentagonal bipyramids, and edges with three equivalent HgF7 pentagonal bipyramids. There are a spread of Ag–F bond distances ranging from 2.16–2.78 Å. Hg2+ is bonded to seven F1- atoms to form HgF7 pentagonal bipyramids that share corners with four equivalent HfF7 pentagonal bipyramids, an edgeedge with one AgF8 hexagonal bipyramid, an edgeedge with one HfF7 pentagonal bipyramid, and edges with two equivalent HgF7 pentagonal bipyramids. There are a spread of Hg–F bond distances ranging from 2.28–2.57 Å. There are seven inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal planar geometry to one Hf4+, one Ag2+, and one Hg2+ atom. In the second F1- site, F1- is bonded in a trigonal planar geometry to three equivalent Hg2+ atoms. In the third F1- site, F1- is bonded in a linear geometry to two equivalent Hf4+ atoms. In the fourth F1- site, F1- is bonded in a linear geometry to one Hf4+ and one Hg2+ atom. In the fifth F1- site, F1- is bonded in a 1-coordinate geometry to one Hf4+ and two equivalent Hg2+ atoms. In the sixth F1- site, F1- is bonded in a linear geometry to two equivalent Ag2+ atoms. In the seventh F1- site, F1- is bonded in a 2-coordinate geometry to one Hf4+, one Ag2+, and one Hg2+ atom.

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2020-05-02. Materials Data on Hf3AgHg3F20 by Materials Project. https://doi.org/10.17188/1705407

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