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DOE OSTI · 1283634

Materials Data on Ba6Ca6Tl5Cu9O29 by Materials Project

Abstract

Ba6Ca6Cu9Tl5O29 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are three inequivalent Ba2+ sites. In the first 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 2.76–3.02 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 2.70–2.97 Å. In the third 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 2.77–3.03 Å. There are three 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 (2.51 Å) and four longer (2.55 Å) Ca–O bond lengths. In the second Ca2+ site, Ca2+ is bonded in a body-centered cubic geometry to eight O2- atoms. All Ca–O bond lengths are 2.51 Å. In the third Ca2+ site, Ca2+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.43 Å) and four longer (2.59 Å) Ca–O bond lengths. There are five inequivalent Cu+2.11+ sites. In the first Cu+2.11+ site, Cu+2.11+ is bonded in a distorted rectangular see-saw-like geometry to five O2- atoms. There are four shorter (1.94 Å) and one longer (2.72 Å) Cu–O bond lengths. In the second Cu+2.11+ site, Cu+2.11+ is bonded in a rectangular see-saw-like geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.94 Å. In the third Cu+2.11+ site, Cu+2.11+ is bonded in a distorted rectangular see-saw-like geometry to five O2- atoms. There are four shorter (1.94 Å) and one longer (2.73 Å) Cu–O bond lengths. In the fourth Cu+2.11+ site, Cu+2.11+ is bonded to five O2- atoms to form distorted CuO5 square pyramids that share a cornercorner with one TlO6 octahedra and corners with four equivalent CuO5 square pyramids. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.95 Å) and one longer (2.69 Å) Cu–O bond lengths. In the fifth Cu+2.11+ site, Cu+2.11+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.94 Å. There are three inequivalent Tl3+ sites. In the first Tl3+ site, Tl3+ is bonded to six O2- atoms to form a mixture of distorted corner and edge-sharing TlO6 octahedra. The corner-sharing octahedral tilt angles are 9°. There are a spread of Tl–O bond distances ranging from 2.04–2.75 Å. In the second Tl3+ site, Tl3+ is bonded to six O2- atoms to form a mixture of distorted corner and edge-sharing TlO6 octahedra. The corner-sharing octahedral tilt angles are 9°. There are a spread of Tl–O bond distances ranging from 2.03–2.75 Å. In the third Tl3+ site, Tl3+ is bonded to six O2- atoms to form TlO6 octahedra that share corners with four equivalent TlO6 octahedra, corners with two equivalent CuO5 square pyramids, and edges with four equivalent TlO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.10 Å) and four longer (2.74 Å) Tl–O bond lengths. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Ba2+, two equivalent Ca2+, and two equivalent Cu+2.11+ atoms to form distorted OBa2Ca2Cu2 octahedra that share corners with ten OBaTl5 octahedra, edges with three OBa2Ca2Cu2 octahedra, and faces with four equivalent OBa2Ca2Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–66°. In the second O2- site, O2- is bonded to four Ca2+ and two equivalent Cu+2.11+ atoms to form distorted OCa4Cu2 octahedra that share corners with eight OBa2Ca2Cu2 octahedra, edges with three OBa2Ca2Cu2 octahedra, and faces with four equivalent OCa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–66°. In the third O2- site, O2- is bonded in a 1-coordinate geometry to four equivalent Ba2+, one Cu+2.11+, and one Tl3+ atom. In the fourth O2- site, O2- is bonded to two equivalent Ba2+, two equivalent Ca2+, and two equivalent Cu+2.11+ atoms to form distorted OBa2Ca2Cu2 octahedra that share corners with ten OBaTl5 octahedra, edges with three OCa4Cu2 octahedra, and faces with four equivalent OBa2Ca2Cu2 octahedra. The corner-sharing octahedra tilt angles range from 1–66°. In the fifth O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Ca2+, and two equivalent Cu+2.11+ atoms. In the sixth O2- site, O2- is bonded to one Ba2+ and five Tl3+ atoms to form a mixture of distorted corner and edge-sharing OBaTl5 octahedra. The corner-sharing octahedra tilt angles range from 9–45°. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to four equivalent Ba2+, one Cu+2.11+, and one Tl3+ atom. In the eighth O2- site, O2- is bonded in a 6-coordinate geometry to four equivalent Ba2+, one Cu+2.11+, and one Tl3+ atom. In the ninth O2- site, O2- is bonded to one Ba2+ and five Tl3+ atoms to form a mixture of distorted corner and edge-sharing OBaTl5 octahedra. The corner-sharing octahedra tilt angles range from 9–44°. In the tenth O2- site, O2- is bonded to four equivalent Ca2+ and two equivalent Cu+2.11+ atoms to form a mixture of corner, edge, and face-sharing OCa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–66°. In the eleventh O2- site, O2- is bonded to two equivalent Ba2+ and four equivalent Tl3+ atoms to form a mixture of corner and edge-sharing OBa2Tl4 octahedra. The corner-sharing octahedral tilt angles are 0°.

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2020-04-30. Materials Data on Ba6Ca6Tl5Cu9O29 by Materials Project. https://doi.org/10.17188/1283634

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