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DOE OSTI · 1271966

Materials Data on Ba2TiOF6 by Materials Project

Abstract

Ba2TiOF6 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten F1- atoms. There are a spread of Ba–F bond distances ranging from 2.69–3.07 Å. In the second Ba2+ site, Ba2+ is bonded in a 11-coordinate geometry to two equivalent O2- and nine F1- atoms. There are one shorter (2.96 Å) and one longer (3.29 Å) Ba–O bond lengths. There are a spread of Ba–F bond distances ranging from 2.63–3.09 Å. Ti4+ is bonded to two equivalent O2- and four F1- atoms to form corner-sharing TiO2F4 octahedra. The corner-sharing octahedral tilt angles are 36°. There is one shorter (1.74 Å) and one longer (2.11 Å) Ti–O bond length. There are a spread of Ti–F bond distances ranging from 1.92–1.99 Å. O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two equivalent Ti4+ atoms. There are six inequivalent F1- sites. In the first F1- site, F1- is bonded to four Ba2+ atoms to form distorted edge-sharing FBa4 trigonal pyramids. In the second F1- site, F1- is bonded in a distorted single-bond geometry to three Ba2+ and one Ti4+ atom. In the third F1- site, F1- is bonded in a distorted single-bond geometry to two Ba2+ and one Ti4+ atom. In the fourth F1- site, F1- is bonded in a distorted single-bond geometry to three Ba2+ and one Ti4+ atom. In the fifth F1- site, F1- is bonded in a distorted single-bond geometry to three Ba2+ and one Ti4+ atom. In the sixth F1- site, F1- is bonded in a 4-coordinate geometry to four Ba2+ atoms.

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2020-07-14. Materials Data on Ba2TiOF6 by Materials Project. https://doi.org/10.17188/1271966

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36 MATERIALS SCIENCE↗