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DOE OSTI · 1722514

Materials Data on Ca11GaSb9 by Materials Project

Abstract

Ca11GaSb9 crystallizes in the orthorhombic Iba2 space group. The structure is three-dimensional. there are six inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 octahedra that share corners with five CaSb6 octahedra, corners with two equivalent CaSb7 pentagonal bipyramids, corners with two equivalent GaSb4 tetrahedra, corners with six equivalent CaSb5 trigonal bipyramids, edges with two equivalent CaSb6 octahedra, faces with two CaSb6 octahedra, and faces with two equivalent CaSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 34–55°. There are a spread of Ca–Sb bond distances ranging from 3.05–3.40 Å. In the second Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 octahedra that share corners with six CaSb6 octahedra, corners with two equivalent CaSb7 pentagonal bipyramids, a cornercorner with one GaSb4 tetrahedra, corners with two equivalent CaSb5 trigonal bipyramids, edges with three CaSb6 octahedra, an edgeedge with one GaSb4 tetrahedra, an edgeedge with one CaSb5 trigonal bipyramid, a faceface with one CaSb6 octahedra, faces with two equivalent CaSb7 pentagonal bipyramids, and a faceface with one CaSb5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 34–54°. There are a spread of Ca–Sb bond distances ranging from 3.09–3.40 Å. In the third Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six Sb+2.78- atoms. There are a spread of Ca–Sb bond distances ranging from 3.08–3.50 Å. In the fourth Ca2+ site, Ca2+ is bonded to seven Sb+2.78- atoms to form distorted CaSb7 pentagonal bipyramids that share corners with six CaSb6 octahedra, corners with two equivalent CaSb7 pentagonal bipyramids, a cornercorner with one GaSb4 tetrahedra, corners with three equivalent CaSb5 trigonal bipyramids, edges with three equivalent CaSb7 pentagonal bipyramids, an edgeedge with one CaSb5 trigonal bipyramid, faces with five CaSb6 octahedra, a faceface with one GaSb4 tetrahedra, and a faceface with one CaSb5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 32–55°. There are a spread of Ca–Sb bond distances ranging from 3.08–3.72 Å. In the fifth Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form CaSb6 octahedra that share corners with six CaSb6 octahedra, corners with four equivalent CaSb7 pentagonal bipyramids, corners with four equivalent CaSb5 trigonal bipyramids, edges with two equivalent CaSb6 octahedra, edges with two equivalent GaSb4 tetrahedra, faces with two equivalent CaSb6 octahedra, and faces with two equivalent CaSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 35–41°. There are a spread of Ca–Sb bond distances ranging from 3.07–3.59 Å. In the sixth Ca2+ site, Ca2+ is bonded to five Sb+2.78- atoms to form distorted CaSb5 trigonal bipyramids that share corners with ten CaSb6 octahedra, corners with three equivalent CaSb7 pentagonal bipyramids, an edgeedge with one CaSb6 octahedra, an edgeedge with one CaSb7 pentagonal bipyramid, an edgeedge with one GaSb4 tetrahedra, a faceface with one CaSb6 octahedra, a faceface with one CaSb7 pentagonal bipyramid, and a faceface with one CaSb5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 33–109°. There are a spread of Ca–Sb bond distances ranging from 3.06–3.44 Å. Ga3+ is bonded to four Sb+2.78- atoms to form GaSb4 tetrahedra that share corners with six CaSb6 octahedra, corners with two equivalent CaSb7 pentagonal bipyramids, edges with four CaSb6 octahedra, edges with two equivalent CaSb5 trigonal bipyramids, and faces with two equivalent CaSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 45–56°. There are two shorter (2.80 Å) and two longer (2.81 Å) Ga–Sb bond lengths. There are five inequivalent Sb+2.78- sites. In the first Sb+2.78- site, Sb+2.78- is bonded in a 7-coordinate geometry to six Ca2+ and one Ga3+ atom. In the second Sb+2.78- site, Sb+2.78- is bonded in a 2-coordinate geometry to eight Ca2+ and one Sb+2.78- atom. The Sb–Sb bond length is 2.89 Å. In the third Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ca2+ and one Ga3+ atom. In the fourth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the fifth Sb+2.78- site, Sb+2.78- is bonded in a 7-coordinate geometry to seven Ca2+ atoms.

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2020-04-29. Materials Data on Ca11GaSb9 by Materials Project. https://doi.org/10.17188/1722514

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36 MATERIALS SCIENCE↗