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DOE OSTI · 1740862

Materials Data on Ca16Sb11 by Materials Project

Abstract

Ca16Sb11 crystallizes in the orthorhombic P2_12_12 space group. The structure is three-dimensional. there are nine inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to four Sb+2.91- atoms to form CaSb4 tetrahedra that share corners with eight CaSb6 octahedra, corners with four CaSb5 trigonal bipyramids, corners with two equivalent CaSb4 trigonal pyramids, and edges with four CaSb6 octahedra. The corner-sharing octahedra tilt angles range from 36–53°. There are two shorter (3.06 Å) and two longer (3.19 Å) Ca–Sb bond lengths. In the second Ca2+ site, Ca2+ is bonded to four Sb+2.91- atoms to form CaSb4 trigonal pyramids that share corners with six CaSb6 octahedra, a cornercorner with one CaSb4 tetrahedra, corners with four CaSb5 trigonal bipyramids, an edgeedge with one CaSb6 octahedra, edges with two CaSb5 trigonal bipyramids, and an edgeedge with one CaSb4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 33–91°. There are a spread of Ca–Sb bond distances ranging from 3.05–3.17 Å. In the third Ca2+ site, Ca2+ is bonded to six Sb+2.91- atoms to form distorted CaSb6 octahedra that share corners with four CaSb6 octahedra, a cornercorner with one CaSb4 tetrahedra, corners with four CaSb5 trigonal bipyramids, corners with two equivalent CaSb4 trigonal pyramids, edges with two CaSb6 octahedra, an edgeedge with one CaSb4 tetrahedra, edges with two CaSb5 trigonal bipyramids, and faces with four CaSb6 octahedra. The corner-sharing octahedra tilt angles range from 28–47°. There are a spread of Ca–Sb bond distances ranging from 3.23–3.40 Å. In the fourth Ca2+ site, Ca2+ is bonded to six Sb+2.91- atoms to form distorted CaSb6 octahedra that share corners with six CaSb6 octahedra, a cornercorner with one CaSb4 tetrahedra, corners with four CaSb5 trigonal bipyramids, corners with two equivalent CaSb4 trigonal pyramids, an edgeedge with one CaSb6 octahedra, an edgeedge with one CaSb4 tetrahedra, edges with two CaSb5 trigonal bipyramids, and faces with four CaSb6 octahedra. The corner-sharing octahedra tilt angles range from 28–50°. There are a spread of Ca–Sb bond distances ranging from 3.22–3.40 Å. In the fifth Ca2+ site, Ca2+ is bonded in a distorted see-saw-like geometry to four Sb+2.91- atoms. There are two shorter (3.14 Å) and two longer (3.25 Å) Ca–Sb bond lengths. In the sixth Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six Sb+2.91- atoms. There are a spread of Ca–Sb bond distances ranging from 3.07–3.73 Å. In the seventh Ca2+ site, Ca2+ is bonded to six Sb+2.91- atoms to form distorted CaSb6 octahedra that share corners with four CaSb6 octahedra, corners with two equivalent CaSb4 tetrahedra, corners with four CaSb5 trigonal bipyramids, corners with two equivalent CaSb4 trigonal pyramids, edges with two CaSb6 octahedra, an edgeedge with one CaSb5 trigonal bipyramid, an edgeedge with one CaSb4 trigonal pyramid, faces with two CaSb6 octahedra, and faces with two equivalent CaSb5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 37–50°. There are a spread of Ca–Sb bond distances ranging from 3.08–3.54 Å. In the eighth Ca2+ site, Ca2+ is bonded to five Sb+2.91- atoms to form CaSb5 trigonal bipyramids that share corners with five CaSb6 octahedra, a cornercorner with one CaSb4 tetrahedra, corners with three equivalent CaSb5 trigonal bipyramids, corners with two equivalent CaSb4 trigonal pyramids, edges with two CaSb6 octahedra, edges with two CaSb5 trigonal bipyramids, an edgeedge with one CaSb4 trigonal pyramid, and faces with two equivalent CaSb6 octahedra. The corner-sharing octahedra tilt angles range from 35–59°. There are a spread of Ca–Sb bond distances ranging from 3.15–3.42 Å. In the ninth Ca2+ site, Ca2+ is bonded to five Sb+2.91- atoms to form CaSb5 trigonal bipyramids that share corners with seven CaSb6 octahedra, a cornercorner with one CaSb4 tetrahedra, corners with three equivalent CaSb5 trigonal bipyramids, corners with two equivalent CaSb4 trigonal pyramids, edges with three CaSb6 octahedra, edges with two CaSb5 trigonal bipyramids, and an edgeedge with one CaSb4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 1–58°. There are a spread of Ca–Sb bond distances ranging from 3.14–3.43 Å. There are seven inequivalent Sb+2.91- sites. In the first Sb+2.91- site, Sb+2.91- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the second Sb+2.91- site, Sb+2.91- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the third Sb+2.91- site, Sb+2.91- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the fourth Sb+2.91- site, Sb+2.91- is bonded in a 6-coordinate geometry to six Ca2+ atoms. In the fifth Sb+2.91- site, Sb+2.91- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the sixth Sb+2.91- site, Sb+2.91- is bonded in a 8-coordinate geometry to eight Ca2+ atoms. In the seventh Sb+2.91- site, Sb+2.91- is bonded in a body-centered cubic geometry to eight Ca2+ atoms.

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2020-04-29. Materials Data on Ca16Sb11 by Materials Project. https://doi.org/10.17188/1740862

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36 MATERIALS SCIENCE↗