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DOE OSTI · 1757249

Materials Data on Na4HfC8O19 by Materials Project

Abstract

Na4HfC8O19 crystallizes in the orthorhombic C222_1 space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.37–2.60 Å. In the second Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.50–2.74 Å. In the third Na1+ site, Na1+ is bonded in a distorted pentagonal bipyramidal geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.29–2.60 Å. Hf4+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Hf–O bond distances ranging from 2.18–2.23 Å. There are four inequivalent C+3.75+ sites. In the first C+3.75+ site, C+3.75+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.24 Å) and one longer (1.29 Å) C–O bond length. In the second C+3.75+ site, C+3.75+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.23 Å) and one longer (1.30 Å) C–O bond length. In the third C+3.75+ site, C+3.75+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.24 Å) and one longer (1.29 Å) C–O bond length. In the fourth C+3.75+ site, C+3.75+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.24 Å) and one longer (1.29 Å) C–O bond length. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Hf4+, and one C+3.75+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Hf4+, and one C+3.75+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to three Na1+ and one C+3.75+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to one Na1+ and one C+3.75+ atom. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ atoms. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Na1+ and one C+3.75+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Na1+, one Hf4+, and one C+3.75+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Na1+ and one C+3.75+ atom. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+, one Hf4+, and one C+3.75+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to three Na1+ atoms.

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2020-09-03. Materials Data on Na4HfC8O19 by Materials Project. https://doi.org/10.17188/1757249

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36 MATERIALS SCIENCE↗