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DOE OSTI · 1276875

Materials Data on Ca21(Mn2Sb9)2 by Materials Project

Abstract

Ca21(Mn2Sb9)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are twelve inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form CaSb6 octahedra that share corners with five CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, corners with three equivalent CaSb6 pentagonal pyramids, corners with three MnSb4 tetrahedra, edges with two equivalent CaSb6 octahedra, a faceface with one CaSb6 octahedra, a faceface with one CaSb7 pentagonal bipyramid, and faces with two equivalent CaSb6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 34–59°. There are a spread of Ca–Sb bond distances ranging from 3.14–3.39 Å. In the second Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form CaSb6 octahedra that share corners with six CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, corners with four MnSb4 tetrahedra, edges with three CaSb6 octahedra, an edgeedge with one MnSb4 tetrahedra, faces with two CaSb6 octahedra, and a faceface with one CaSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 33–70°. There are a spread of Ca–Sb bond distances ranging from 3.24–3.50 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 3.06–3.73 Å. In the fourth Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 octahedra that share corners with five CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, corners with two equivalent CaSb6 pentagonal pyramids, corners with two MnSb4 tetrahedra, edges with two CaSb6 octahedra, an edgeedge with one CaSb6 pentagonal pyramid, edges with two MnSb4 tetrahedra, faces with two CaSb6 octahedra, and a faceface with one CaSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 34–59°. There are a spread of Ca–Sb bond distances ranging from 3.07–3.39 Å. In the fifth Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 octahedra that share corners with seven CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, a cornercorner with one CaSb6 pentagonal pyramid, corners with two MnSb4 tetrahedra, edges with two CaSb6 octahedra, an edgeedge with one MnSb4 tetrahedra, faces with three CaSb6 octahedra, a faceface with one CaSb7 pentagonal bipyramid, and a faceface with one MnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 33–54°. There are a spread of Ca–Sb bond distances ranging from 3.15–3.45 Å. In the sixth Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 octahedra that share corners with six CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, a cornercorner with one CaSb6 pentagonal pyramid, corners with three MnSb4 tetrahedra, edges with two CaSb6 octahedra, an edgeedge with one CaSb6 pentagonal pyramid, an edgeedge with one MnSb4 tetrahedra, faces with two CaSb6 octahedra, and a faceface with one CaSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 36–50°. There are a spread of Ca–Sb bond distances ranging from 3.10–3.45 Å. In the seventh 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 3.12–3.83 Å. In the eighth Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 pentagonal pyramids that share corners with seven CaSb6 octahedra, corners with two CaSb7 pentagonal bipyramids, a cornercorner with one MnSb4 tetrahedra, edges with two CaSb6 octahedra, an edgeedge with one CaSb6 pentagonal pyramid, an edgeedge with one MnSb4 tetrahedra, faces with two equivalent CaSb6 octahedra, a faceface with one CaSb7 pentagonal bipyramid, and faces with two equivalent CaSb6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 33–50°. There are a spread of Ca–Sb bond distances ranging from 3.10–3.38 Å. In the ninth 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 3.11–3.72 Å. In the tenth Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven Sb+2.78- atoms. There are a spread of Ca–Sb bond distances ranging from 3.04–3.79 Å. In the eleventh Ca2+ site, Ca2+ is bonded to seven Sb+2.78- atoms to form CaSb7 pentagonal bipyramids that share corners with four CaSb6 octahedra, corners with two equivalent CaSb6 pentagonal pyramids, a cornercorner with one MnSb4 tetrahedra, an edgeedge with one CaSb7 pentagonal bipyramid, an edgeedge with one MnSb4 tetrahedra, faces with six CaSb6 octahedra, and faces with two equivalent MnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–51°. There are a spread of Ca–Sb bond distances ranging from 3.27–3.57 Å. In the twelfth 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 CaSb6 pentagonal pyramids, corners with two MnSb4 tetrahedra, an edgeedge with one CaSb7 pentagonal bipyramid, faces with four CaSb6 octahedra, faces with two equivalent CaSb6 pentagonal pyramids, and faces with two equivalent MnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–57°. There are a spread of Ca–Sb bond distances ranging from 3.29–3.67 Å. There are three inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded to four Sb+2.78- atoms to form MnSb4 tetrahedra that share corners with seven CaSb6 octahedra, a cornercorner with one CaSb6 pentagonal pyramid, a cornercorner with one MnSb4 tetrahedra, edges with three CaSb6 octahedra, an edgeedge with one CaSb6 pentagonal pyramid, an edgeedge with one MnSb4 tetrahedra, and faces with two CaSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 37–57°. There are a spread of Mn–Sb bond distances ranging from 2.75–2.88 Å. In the second Mn2+ site, Mn2+ is bonded to four Sb+2.78- atoms to form MnSb4 tetrahedra that share corners with six CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, corners with two equivalent MnSb4 tetrahedra, edges with two equivalent CaSb6 octahedra, an edgeedge with one CaSb7 pentagonal bipyramid, an edgeedge with one MnSb4 tetrahedra, and faces with two equivalent CaSb6 octahedra. The corner-sharing octahedra tilt angles range from 44–95°. There are a spread of Mn–Sb bond distances ranging from 2.73–2.79 Å. In the third Mn2+ site, Mn2+ is bonded to four Sb+2.78- atoms to form MnSb4 tetrahedra that share corners with eight CaSb6 octahedra, corners with two CaSb7 pentagonal bipyramids, edges with two equivalent CaSb6 octahedra, and an edgeedge with one MnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–60°. There are a spread of Mn–Sb bond distances ranging from 2.76–2.80 Å. There are fourteen inequivalent Sb+2.78- sites. In the first Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ca2+ and one Sb+2.78- atom. The Sb–Sb bond length is 2.94 Å. In the second Sb+2.78- site, Sb+2.78- is bonded in a 7-coordinate geometry to eight Ca2+ and one Mn2+ atom. In the third Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to six Ca2+ and two Mn2+ atoms. In the fourth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ca2+ and one Mn2+ atom. In the fifth Sb+2.78- site, Sb+2.78- is bonded in a 4-coordinate geometry to seven Ca2+ and two equivalent Mn2+ atoms. In the sixth Sb+2.78- site, Sb+2.78- is bonded in a 7-coordinate geometry to seven Ca2+ and one Mn2+ atom. In the seventh Sb+2.78- site, Sb+2.78- is bonded in a 2-coordinate geometry to seven Ca2+ and one Sb+2.78- atom. The Sb–Sb bond length is 2.91 Å. In the eighth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the ninth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the tenth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ca2+ and one Sb+2.78- atom. The Sb–Sb bond length is 2.98 Å. In the eleventh Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the twelfth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to seven Ca2+ and one Mn2+ atom. In the thirteenth Sb+2.78- site, Sb+2.78- is bonded in a 7-coordinate geometry to five Ca2+, one Mn2+, and one Sb+2.78- atom. The Sb–Sb bond length is 2.94 Å. In the fourteenth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to six Ca2+ and three Mn2+ atoms.

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2020-04-30. Materials Data on Ca21(Mn2Sb9)2 by Materials Project. https://doi.org/10.17188/1276875

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