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DOE OSTI · 1204629

Materials Data on Ca21(Mn2Sb9)2 by Materials Project

Abstract

Ca21(Mn2Sb9)2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are eleven inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to seven Sb+2.78- atoms to form distorted CaSb7 pentagonal bipyramids that share corners with four CaSb6 octahedra, a cornercorner with one CaSb6 pentagonal pyramid, corners with three MnSb4 tetrahedra, corners with two equivalent CaSb5 trigonal bipyramids, an edgeedge with one CaSb7 pentagonal bipyramid, faces with five CaSb6 octahedra, a faceface with one CaSb6 pentagonal pyramid, a faceface with one MnSb4 tetrahedra, and a faceface with one CaSb5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 31–60°. There are a spread of Ca–Sb bond distances ranging from 3.05–3.65 Å. In the second 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, a cornercorner with one CaSb6 pentagonal pyramid, corners with three MnSb4 tetrahedra, corners with two equivalent CaSb5 trigonal bipyramids, edges with two CaSb6 octahedra, faces with two CaSb6 octahedra, a faceface with one CaSb7 pentagonal bipyramid, and a faceface with one CaSb6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 37–55°. There are a spread of Ca–Sb bond distances ranging from 3.15–3.38 Å. In the third 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 3.18–3.67 Å. In the fourth Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 octahedra that share corners with four CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, a cornercorner with one CaSb6 pentagonal pyramid, corners with three MnSb4 tetrahedra, a cornercorner with one CaSb5 trigonal bipyramid, edges with three CaSb6 octahedra, an edgeedge with one CaSb6 pentagonal pyramid, an edgeedge with one MnSb4 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 33–53°. There are a spread of Ca–Sb bond distances ranging from 3.08–3.35 Å. In the fifth 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 3.07–3.88 Å. In the sixth 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, corners with two equivalent CaSb5 trigonal bipyramids, edges with two equivalent CaSb6 octahedra, an edgeedge with one CaSb6 pentagonal pyramid, edges with two MnSb4 tetrahedra, an edgeedge with one CaSb5 trigonal bipyramid, a faceface with one CaSb6 octahedra, and a faceface with one CaSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 34–53°. There are a spread of Ca–Sb bond distances ranging from 3.04–3.43 Å. In the seventh Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form distorted CaSb6 pentagonal pyramids that share corners with seven CaSb6 octahedra, a cornercorner with one CaSb7 pentagonal bipyramid, corners with two MnSb4 tetrahedra, a cornercorner with one CaSb5 trigonal bipyramid, 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 30–44°. There are a spread of Ca–Sb bond distances ranging from 3.09–3.42 Å. In the eighth Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to five Sb+2.78- atoms. There are a spread of Ca–Sb bond distances ranging from 3.07–3.49 Å. In the ninth Ca2+ site, Ca2+ is bonded to five Sb+2.78- atoms to form distorted CaSb5 trigonal bipyramids that share corners with nine CaSb6 octahedra, corners with two equivalent CaSb7 pentagonal bipyramids, a cornercorner with one CaSb6 pentagonal pyramid, a cornercorner with one MnSb4 tetrahedra, an edgeedge with one CaSb6 octahedra, an edgeedge with one MnSb4 tetrahedra, an edgeedge with one CaSb5 trigonal bipyramid, a faceface with one CaSb6 octahedra, and a faceface with one CaSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 31–111°. There are a spread of Ca–Sb bond distances ranging from 3.10–3.36 Å. In the tenth 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 three MnSb4 tetrahedra, corners with three equivalent CaSb5 trigonal bipyramids, edges with two CaSb6 octahedra, edges with two MnSb4 tetrahedra, a faceface with one CaSb6 octahedra, a faceface with one CaSb7 pentagonal bipyramid, and a faceface with one CaSb6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 33–55°. There are a spread of Ca–Sb bond distances ranging from 3.18–3.51 Å. In the eleventh Ca2+ site, Ca2+ is bonded to six Sb+2.78- atoms to form CaSb6 octahedra that share corners with six CaSb6 octahedra, corners with two equivalent CaSb6 pentagonal pyramids, corners with two equivalent CaSb5 trigonal bipyramids, edges with two equivalent CaSb6 octahedra, edges with two MnSb4 tetrahedra, faces with two equivalent CaSb6 octahedra, and faces with two equivalent CaSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 34–42°. There are a spread of Ca–Sb bond distances ranging from 3.05–3.55 Å. There are four 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 six CaSb6 octahedra, corners with two equivalent CaSb7 pentagonal bipyramids, corners with two equivalent CaSb6 pentagonal pyramids, edges with three CaSb6 octahedra, and an edgeedge with one MnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–54°. There are two shorter (2.78 Å) and two longer (2.80 Å) Mn–Sb bond lengths. 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, corners with two equivalent CaSb7 pentagonal bipyramids, edges with two equivalent CaSb6 octahedra, edges with two equivalent CaSb6 pentagonal pyramids, and edges with two MnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–55°. There are two shorter (2.75 Å) and two longer (2.86 Å) Mn–Sb bond lengths. In the third Mn2+ site, Mn2+ is bonded to four Sb+2.78- atoms to form distorted MnSb4 tetrahedra that share corners with four CaSb6 octahedra, corners with two equivalent CaSb7 pentagonal bipyramids, corners with two equivalent CaSb6 pentagonal pyramids, corners with two equivalent CaSb5 trigonal bipyramids, edges with four CaSb6 octahedra, and edges with two MnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 32–35°. There are two shorter (2.77 Å) and two longer (2.80 Å) Mn–Sb bond lengths. In the fourth Mn2+ site, Mn2+ is bonded to four Sb+2.78- atoms to form MnSb4 tetrahedra that share corners with six CaSb6 octahedra, edges with three CaSb6 octahedra, an edgeedge with one MnSb4 tetrahedra, edges with two equivalent CaSb5 trigonal bipyramids, and faces with two equivalent CaSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 43–55°. There are two shorter (2.73 Å) and two longer (2.86 Å) Mn–Sb bond lengths. There are nine inequivalent Sb+2.78- sites. In the first Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the second Sb+2.78- site, Sb+2.78- is bonded in a 7-coordinate geometry to eight Ca2+ atoms. In the third Sb+2.78- site, Sb+2.78- is bonded in a 7-coordinate geometry to six Ca2+ and one Mn2+ atom. In the fourth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to seven Ca2+ and two Mn2+ atoms. In the fifth Sb+2.78- site, Sb+2.78- is bonded in a 7-coordinate geometry to five Ca2+ and two Mn2+ atoms. In the sixth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to six Ca2+ and two Mn2+ atoms. In the seventh Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ca2+ and one Mn2+ atom. In the eighth 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 ninth 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 2.97 Å.

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2020-04-29. Materials Data on Ca21(Mn2Sb9)2 by Materials Project. https://doi.org/10.17188/1204629

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