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DOE OSTI · 1686733

Materials Data on Ba4Ca4Cu6Hg2O17 by Materials Project

Abstract

Ba4Ca4Cu6Hg2O17 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. All Ba–O bond lengths are 2.83 Å. In the second Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.63–2.98 Å. There are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.44 Å) and four longer (2.52 Å) Ca–O bond lengths. In the second Ca2+ site, Ca2+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.44 Å) and four longer (2.54 Å) Ca–O bond lengths. There are four inequivalent Cu+2.33+ sites. In the first Cu+2.33+ site, Cu+2.33+ is bonded in a square co-planar geometry to five O2- atoms. There are four shorter (1.93 Å) and one longer (2.76 Å) Cu–O bond lengths. In the second Cu+2.33+ site, Cu+2.33+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.93 Å. In the third Cu+2.33+ site, Cu+2.33+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.93 Å. In the fourth Cu+2.33+ site, Cu+2.33+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.93 Å. Hg2+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (2.06 Å) and two longer (2.73 Å) Hg–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to four Ba2+, one Cu+2.33+, and one Hg2+ atom. In the second O2- site, O2- is bonded in a 6-coordinate geometry to two Ba2+, two Ca2+, and two equivalent Cu+2.33+ atoms. In the third O2- site, O2- is bonded to four Ca2+ and two Cu+2.33+ atoms to form a mixture of edge, face, and corner-sharing OCa4Cu2 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth O2- site, O2- is bonded to two equivalent Ba2+ and four equivalent Hg2+ atoms to form corner-sharing OBa2Hg4 octahedra. The corner-sharing octahedral tilt angles are 0°.

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2020-04-29. Materials Data on Ba4Ca4Cu6Hg2O17 by Materials Project. https://doi.org/10.17188/1686733

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