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DOE OSTI · 1724817

Materials Data on RbTa7(CuO7)3 by Materials Project

Abstract

RbTa7(CuO7)3 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 8-coordinate geometry to ten O2- atoms. There are a spread of Rb–O bond distances ranging from 3.22–3.54 Å. In the second Rb1+ site, Rb1+ is bonded to twelve O2- atoms to form distorted RbO12 cuboctahedra that share edges with twelve TaO6 octahedra. There are a spread of Rb–O bond distances ranging from 3.19–3.48 Å. There are four inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form distorted corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 34–48°. There are a spread of Ta–O bond distances ranging from 1.96–2.03 Å. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and edges with two equivalent RbO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 10–34°. There are a spread of Ta–O bond distances ranging from 1.92–2.02 Å. In the third Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and an edgeedge with one RbO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 23–47°. There are a spread of Ta–O bond distances ranging from 1.90–2.15 Å. In the fourth Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and an edgeedge with one RbO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 22–42°. There are a spread of Ta–O bond distances ranging from 1.90–2.13 Å. There are six inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.94 Å) and two longer (1.98 Å) Cu–O bond length. In the second Cu2+ site, Cu2+ is bonded in a 4-coordinate geometry to six O2- atoms. There are a spread of Cu–O bond distances ranging from 1.97–2.52 Å. In the third Cu2+ site, Cu2+ is bonded in a distorted square co-planar geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.98 Å. In the fourth Cu2+ site, Cu2+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All Cu–O bond lengths are 2.11 Å. In the fifth Cu2+ site, Cu2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are two shorter (2.03 Å) and two longer (2.12 Å) Cu–O bond lengths. In the sixth Cu2+ site, Cu2+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are two shorter (1.97 Å) and two longer (2.17 Å) Cu–O bond lengths. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two Rb1+ and two equivalent Ta5+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Rb1+ and two equivalent Ta5+ atoms. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Ta5+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ta5+ and one Cu2+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Ta5+ and one Cu2+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Ta5+ and one Cu2+ atom. In the seventh O2- site, O2- is bonded in a linear geometry to two equivalent Ta5+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ta5+ and one Cu2+ atom. In the ninth O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Ta5+ and one Cu2+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ta5+ and one Cu2+ atom. In the eleventh O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Ta5+ atoms. In the twelfth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Rb1+ and two Ta5+ atoms. In the thirteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two Rb1+ and two Ta5+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ta5+ and one Cu2+ atom. In the fifteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ta5+ and one Cu2+ atom. In the sixteenth O2- site, O2- is bonded in a linear geometry to two equivalent Ta5+ atoms. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ta5+ and one Cu2+ atom. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ta5+ and two Cu2+ atoms.

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2020-04-29. Materials Data on RbTa7(CuO7)3 by Materials Project. https://doi.org/10.17188/1724817

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